If any member here knows the answer, may reply to this question.]]>

well not sure why we need 3 different coins other than confusion

also each toss at least 2 coins have to have the same face

frankly not sure how any of these choices work

didn't want to surf online better to stumble thru it here and learn it better

oh.. one nice thing about this new format... don't have to continuely log in]]>

ok I still don't know where the (0.2) comes from]]>

This is how approached .

200 tagged : Population 14 tagged : 100

(200x100/14)= Estimated Population = 1,429

I wonder if this is right !

This problem I used combinations for 10 walls for one color and 4 walls for one color; Here my calculations:

14 walls in total, 10 walls in one colour and the rest (4 walls) in another colour.

For 10 walls: nCr = 14C10 = n!/(n-r)!r! = (14)!/(14-10)!(10)! = (14)!/(4)!(10)...

In how many ways can Ben paint his apartment?]]>

a) What is the probability that exactly 8 of them are over the age of 65?

b) P (less than 10 are over 65) =

c) P (more than 10 are over 65) =

d) P (11 or fewer are over 65) =

e) P ( more than 11 are over 65) =]]>

X 0 1 2 3 4

P(X) 0.1 0.2 0.4 0.2 0,1

a) Find the probability of 1 tire with low air pressure P (1) =

b) Find the probability of more than 2 tires having low air pressure P (more than 2) =

c) P (all 4 tires) =

d) Compute the expected number of tires...

Find the probability of 1 tire with low air pressure P (1)]]>

2. Tom is having a 4/19 lottery as a fundraiser; 4 winning numbers will be randomly selected without replacement out of the numbers from 1 to 19 inclusive. (similar to Ontario’s 6/49, with smaller numbers) The prizes are described below. For the questions below, define an appropriate random variable X.

Tickets Prize

All 4 winning numbers 1000 dollars

Any 3 of the winning numbers 100

Any 2 of the winning numbers 10

Any 1 of the winning...

Tom claims that there is over a 60% chance that you can win a 10 or 5 prize. Is his claim correct]]>

I'm not sure if this is the correct forum so if I need to post elsewhere please let me know.

I'm having trouble with calculating the possible combinations for six digit license plates, numbers 0-9 and letters a-z.

I know the overall combinations are 1,947,792 when repetition is allowed and there are no other requirements, but I'm getting stuck when I have to limit three spots to only numbers and the other three to only letters.

I don't have a fancy calculator. Can someone let me...

possible combinations for six digit license plates, numbers 0-9 and letters a-z.]]>

Brute-forcing will take about a whole day, I think. If 4 students receive 1 cupcake and the other one receive 27, that's already 4 combinations. If there are 3 1's, the other two might be 3 and 25, 5, and 23, 7 and 21, etc. Is there more efficient way?]]>

I am involved with a Rotary Club which uses a dice game to raise funds at various events. We want to look carefully at the probabilities of throwing dice. Can you tell me please in very basic layman's terms the odds on the same number being thrown on 4 out of 7 dice in one throw (which number doesn't matter). Then for 5, 6 and 7 the same, and finally 7 sixes.

We would like to use the formula then to look also at changing the number of dice and the number of the same digit required...

Dice throwing probabilities]]>

There are 100 socks in a drawer. 84 are Red. 16 are White. If you are blindfolded & have to choose 11 socks randomly, what is the odds or what it more likely:

1) Picking 11 reds in a row.

OR

2) Picking 10 whites and 1 red

I know the answer is 2, but just need the correct calculation, math and percentage behind each option.

Thanks in advance.]]>

A. 1/16

B. 1/8

C. 1/4

D. 1/2

I thought the answer was 15/240 (the probability of Mr. Aziz's family getting the doorprize) times 1/30 (the main one among the doorprize) and it results in 1/480, but it's not in the options. Is the book wrong or am I the one who...

[ASK] Probability of Getting the Main Doorprize]]>

First time posting and as English is not my native language, I'd like to apologize in advance for any linguistic errors I make.

Yesterday, I received a case which sounded really easy to calculate but for some reason I can't get my head around it.

This is the case:

In a shipping company for clothes there are 10 different orders being handled at the same time. These orders all have 4 clothes, which means there are 40 clothes in total that have to be sorted. At random these clothes...

Probability calculation of dependent events with limitations]]>

Sorry if this is the wrong section of the forums, but I figured that questions about mutually exclusive events are relevant to probability.

Two events are mutually exclusive if both events cannot occur at the same time. In other words, two events are mutually exclusive if the probability of both events occurring at the same time is 0.

I guess I'll use an example with fair six-sided dice to try and explain where my confusion lies.

Confused About Mutual Exclusivity with More Than Two Events]]>

I do not know where to start with this one.]]>

1. all 5 dice rolls are the same

2. 4 dice rolls are the same

3. the dice rolls are in sequence (1-5 or 2-6) -order does not matter

4. two pairs of dice are the same (ex: 1 1 4 4 3)

5. the result is one pair and the other three are the same (ex: 1 1 1 6 6)

So far, my understanding of the problem has been the ff:

1. 1/6^5

2. 150/6^5

3.(5!+5!)/6^5...

Find the probability all 5 dice rolls are the same]]>

So say a person takes this HIV test and they fit into the demographic of the CDC statistic. If 1/13 people who are HIV positive tests...

Probability of Having a Disease]]>

The probability is 1/6, so the expected frequency is 1/6 × 100, but that results in a fraction (16 2/3). Do we need to round it up or down? Is the answer 16 or 17?]]>

If there’s 10% chance of getting cancer from microwaves, and 3% of the population gets cancer, what is the probability that a certain person who have cancer and was exposed to microwaves got it as a result from his exposure, if 15% of the population are exposed to microwaves.]]>

Kindly, can anyone solve the following:

How many combinations:

8 colors, which each can be used twice in the following grid

1 3 5 7

2 4 6 8

where a color can only appear like this

1 with 5

3 with 7

2 with 6

4 with 8

So, non-valid combinations would be

1 with 2

1 with 3

2 with 3

2 with 4 etc. etc.

Thanks a lot!]]>

So, (C1,C1) (C2,C2) (C3,C3) (C4,C4) (C5,C5) (C6,C6) (C7,C7) (C8,C8) is what he ended up with.

He stated this was good because there was an equal chance of getting them. I thought that this was highly unusual, and suggested there was no randomness since he received two of every possible item.

That brings me to the title...

Need to find the probability of receiving 8 pairs of identical boxes choosing from 8 items 16 times?]]>

Please help me understand with an example.

Say I roll five six-sided dice all at once, with die faces numbered 1 through 6.

I want to determine the probability of AT LEAST three 6s occurring. First, is this the best way to set up the equation?

P(at least three 6s) = 1 - P(zero 6s) - P(exactly one 6) - P(exactly two 6s)

Or can the equation be better setup by subtracting AT LEAST occurrences?

I know this much...

Find the probability of AT LEAST three 6s occurring when rolling five six-sided dice all at onc]]>

Let's say I have a score of effectiveness for wheat fertiliser products (such as a growth rate), along with measurements of various associated behaviours in the crop (improved absorption levels...

Using ratios to calculate weights in a weighted average (or not)]]>

The problems is asking whether there are more men being paid more than £32 000 than men

being paid less than £32 000. I'm leaning to saying that its not possible to make this judgement due to the position of mean. All the long left hand whisker is illustrating is the spread of data.\

If someone could help me understand it would be much appreciated.

MJM]]>

a) all throws are different

b) two throws are the same (a double)

c) three throws are the same (a treble)

d) four throws are the same (a quartet)

e) all five throws are the same (quintet).

So far i have worked out that:

a) (1/6)^5 . 6!/5!1! = 1/1296

b) 6 . (1/6)^2 . (5/6)^3 . 5!/3!2! = 1250/1296

c) 6 . (1/6)^3 . (5/6)^2 . 5!/2!3! = 250/1296

d) 6. (1/6)^4 . (5/6)^1 . 5!/4!1! = 25/1296...

Find the probability where two throws are the same (a double) when throwing a 6-sided die 5 times]]>

a. If he chooses randomly, how many ways can Akio form his starting lineup?

b. How many of those teams have Sidney playing in the libero position?

c. If Akio chooses starting teams...

If he chooses randomly, how many ways can Akio form his starting lineup]]>

Question 9:

Let \(\displaystyle A = (1,2,3,4)\) and \(\displaystyle Z = (1,2,3,4,5,6,7,8,9,10)\), if a subset

a) \(\displaystyle P (B⊂A)\) B is a proper subset of A

b) \(\displaystyle P (A∩B = Ø)\) A intersection B =empty set

Appreciate]]>

We know that 20% of the male customers buy book A at least once a week, 55% buy book B at least once a week, 25% buy book C at least once a week and 15% buy book D at least once in a month.

We also know that 32% of the female customers by book A at least once a week, 80% buy book B at least once a week, 40% buy book C at least once a week and 65% buy book D at least once a week.

The ratio of male customers to female is 3 to 1...

Conditional probability given 2 scenarios: probability of meeting male and a female in the shop]]>

I have two really simple questions that I have already answered but the teacher wants more info. I am really stumped and I am not looking for the answers so much as an explanation on how to better answer the questions. I will copy and paste the problems and my answers (in bold black) as well as their comments (in red) below. I also have attached a pic of the ols regression table I am working from. ANY help or comment is welcome. Please help!

Robin Anderson...

Levels of Measurement, Basic OLS Regression Questions]]>

the principal of a middle school claims that test scores of the seventh-grade at her school vary less than the test scores of seventh- graders at the neighboring school, which has a variation described by o(standard deviation ) = 14.7

explain your answer]]>

A factory’s product is sampled once per month every month by its quality inspection team. The factory is allowed up to 2 product failures per ROLLING 12 month period (i.e. Mar-Feb, April-Mar etc) but if it fails 3 times it must close its production line. The probability of failing each sample is 0.05. Work out the probability that (given that the...

How to exclude combinations for defined sequences?]]>

11

12

23

47

31

49

11

11

36

31

39

47

31

46

33

25

48

35

0

15]]>

Thanks for your help in advance!]]>

I tried to get the limits from the normal distributions that were given. If I was doing it right, I had

$90\leq X \leq 130 $

$1.9\leq Y \leq 2.9$

for X and Y.

I think my main problem is...

Calculating the expected value and variance of continuous multi-variable function]]>

So, if the last 10 flips were "H,T,T,H,H,T,T,H,H,H".

What would the probability be for the 11th flip to be the same as 10th flip?]]>

----------------------------------------------------------------------------------------------------

My attempt:

G1: First screw is good. G2: Second screw is good

G1A: First screw comes from A. G1B...

Two screws are inspected and the first is found to be good. What is the probability that the second is also good]]>

Answer given is 143. But my logic is for any sum, at least 2 numbers are needed. So, there are $\binom{15} {2} + \binom{15}{3}+...\binom{15}{15} $ distinct sums.

So, I think answer 143 is wrong.

What is your opinion?]]>

Kindly can someone solve these with explanation?

1. In how many ways can four French books, two English books and three German books be arranged on a shelf so that all books in same language are together.

2. How many different arrangements can be formed of the word "equation" if all the vowels are to be kept together?

3. A combination lock has five wheels, each labeled with the ten digits from 0 to 9. How many five number opening combinations are possible,

(i) assuming no...

How many different arrangements can be formed of the word "equation" if all the vowels are to be kept together?]]>

Previously, the government conducted a lottery to award visas to 20,000 advanced-degree holders first. Those who weren't chosen then got a second chance with the other H-1B petitions in a larger 65,000-visa lottery. This year, instead of conducting the advanced-degree lottery first, USCIS will run the...

What’s the increased probability for a masters student given that there are 3 lottery attempts]]>

Calculating a weighted mean?]]>

The layout of the data is as follows:

A B C D

Order Accurate- 315 277 234 120

Order not - 34 50 35 18

accurate

Like I said previously this is an or problem and this means it is an addition rule problem. The problem wants me to compute

the probability that whenever a single order is selected what is the probability that this probability is from...

probability that whenever a single order is selected what is the probability that this probability is from restaurant A or C or]]>

2.A darts player finds that on average he hits the bullseye 4 times out of 5. Calculate the...

Find the probability that in a random sample of 4 shots, he will miss the bullseye at least 3 times]]>

Here is the problem:

That is the p.d.f. of a random variable X.

I have to find the cdf.

I don't know which I should do so I tried it two ways. First:

$\int_{-1}^{1} \ \frac{2}{\pi(1+x^{2})} dx = {{\frac{2}{\pi} arctan(x)]}^{1}}_{-1}=1$

Second:

$\int_{-1}^{x} \ \frac{2}{\pi(1+t^{2})} dt = {{\frac{2}{\pi} arctan(x)]}^{x}}_{-1}=\frac{2(arctan(x)+\frac{\pi}{4}}{\pi}$

Which one is the required CDF...

Given probability density function find its cumulative distribution function]]>

I want to know the odds for the game Paper Rock Scissors.

What are the odds of winning

What are the odds of drawing

Thanks in advance ]]>

a manufacturer of laptop computers claims that only 1% of their computers are defective. In a sample of 600 computers, it was found that 3% were defective. If the proportion of defectives were really only 1%, there would be less than 1 chance in 1000 of getting such a large proportion of defective laptops in the sample. Is...

Is there statistically significant evidence against the manufacturer's claim ? Why or why not?]]>

Internet Users (Per 100) Award Winners (Per 10 Million)

78.2 5.5

79.5 9

55.8 3.3

67.2 1.6

76.9 10.9

39.1...

Linear Correlation]]>

There are 4 people, each of whom has one deck of cards with 500 cards that are numbered from 1 to 500 with no duplicates.

Each person draws a card from his deck and I would like to calculate the probability of the event that "the arithmetic mean of the number on the 4 cards is 405".

How to make that?

Some explanation is welcome.]]>

Firstly, what a wonderful place for people to help one and other. I am glad that I have stumbled across : )

I have posted this query in advanced because to me there it is advanced but if it is basic to others then please excuse me.

I can easily work out the probability of something happening every time at general probability or odds but I fall down when working out the probability of it happening a lesser number of times.

Likelihood of things happening on with regularity depending on initial probability]]>

Year 1st company sales ( In millions) Month 2nd company sales( In millions)

2010 22...

Compare between the different approaches of forecasting and advise by return the one you suggest]]>

Answer the following Questions:

Hypotheses - Formulate null and alternative hypotheses. What do you think is the relationship between IQ scores and GPA?]]>

1. A ball is randomly selected from the tank and it was frosted. What is the probability that the ball was labeled?

2. The 1st ball was frosted and the 2nd one was mild (not frosted) What is the probability if we would do two trials?

3. To select a ball was frosted and this ball was not returned to the tank, and select the 2nd one...

What is the probability that the ball was labeled]]>

a. find P(at least 1 woman).

b. find P(0 men)

c.Find P(all men or all women).

a coin purse contains 10 pennies, 4 dimes, and 4 quarters. four coins are selected at random with replacement. Write your answer as a fully reduced fraction.

a. find P ( dime then penny then penny then quarter).

b. find P(quarter then penny then nickel then nickel)

c...

find P(at least 1 woman)]]>

a card is drawn from a standard deck with 52 cards. Find P(spade or face card or 3 or club). Write your answer as a fully reduced fraction?

5)

five cards are drawn from a standard deck with 52 cards without replacement. find the probability that the first card is a heart, the second is a spade, the third is a spade, the fourth is a heart, and the fifth is a diamond. Write your answer as a fully reduced fraction]]>

I'm working on an application and I have a problem that I've been wrecking my brain over. The best way I can explain it is through a game.

There are 4 bags with numbered balls in each (the total number of balls in each bag is irrelevant). You have to guess the number that is going to be selected from each bag and you will win a prize if you match all 4 selections and also if you match 3 out of 4. You are also allowed to play combinations, meaning you can have multiple guesses for...

Calculating total possible matching combinations remaining]]>

I would like to ask, if I am right with my computation.

Let´s have a set of integers from 0 to 12. We start at 0 and we can go to 1 with the probability 1. From 1 we can go to 1 or back to 0, both with probability 0.5. When we start at zero, how many steps (exp. number of them) do we need to go until 12?

My way of solving:

We start at 0 ... there is only one possibity - to go to the 1 with probability 1

From 1, we can go to the 0 (P=$\frac{1}{2}$) or to the 2 (P=$\frac{1}{2}$)...

Expected value of steps]]>

My apologies if the title is confusing; I don't really know how to explain what I am trying to do or what label this problem would fall under.

We have a magic bag, and inside the magic bag are an unknown/unlimited amount of coins.

There are 100 different types of coins, but we are only interested in the iron, bronze, silver and gold coins, so we have bundled the other 96 types together as "other".

We performed an experiment by taking one coin at a time from the...

Calculating overall percentage/probability from multiple categories?]]>

Question 5 is causing me issues!

View attachment mathsquestions.pdf]]>

You roll two fair die. What is the probability of one of the dice showing 2 or the sum being at least 8?

I thought it should be: 15/36 for the sum being at least 8 and 10/36 for exactly one dice showing 2, but it tells me it is wrong. I got these numbers by constructing a chart that showed the outcomes of the 2 die rolls.]]>

Chance performance on a yes/no task where no is correct 2/3 of the time?]]>

Suppose P(Q)=5/31 , P(R)= 7/31 , P(Q intersect R)=3/31

Find the value of:

A) P(Q') B) P(Q union R) C) P(R')]]>

Assume that a gambler plays a fair game where he can win or lose 1 dollar in each round . His initial stock is 200 dollar. He decides a priory to stop gambling at the moment when he either has 500 dollars or 0 dollars in his stock. Time is counted by the number of rounds played.

i) show that the probability that he will never stops gambling is zero

ii ) Compute the probability that at the time when he stops gambling he has 500 dollars and the...

show that the probability that he will never stops gambling is zero]]>

]]>

Plenty of food and water for millions

Cosmic ray protection

Only lights used are infrared, visible, UVA, and UVB

Monogamy

So first off the starting population is around 45,000. While some are subfertile, some are infertile, and some are fertile or super...

Population formula part 1: Birth]]>

For this problem, assume 10 males audition, one of them being Dale, 7 females audition, one of them being Margaret, and 4 children audition. The casting director has 3 male roles available, 1 female role available, and 2 child roles available.

1) How many different ways can these roles be filled if exactly one of Dale and Margaret gets a part?

2) What is the probability (if the roles are filled at random) of both Dale and Margaret...

How many different ways can these roles be filled if exactly one of Dale and Margaret gets a part?]]>

There are 8 mice in a cage... 3 white males, 3 gray females, and 2 gray males. Two mice are selected simultaneously and at random, and their colors are noted. Find the pr that at least one mouse is a male given that exactly ones is grey.

I am not sure if I set up the tree correctly, so I just went by with combinations. I did: C(3,1)C(2,1)/C(3,1)C(2,1)+C(3,1)C(3,1), but that did not work. Why was that approach wrong?]]>

then we have sufficient evidence to reject the null hypothesis at 0.05 level of significance.]]>

However, if I were to go through a list of every infectious illness and decide whether or not it is allowed, should I have a death rate limit? Is there a point at which pregnancy rate and more importantly birth rate, can't overcome the death rate from infection assuming an average death rate of 8 per 1000 per year from other causes?

So is there a point at which death rate from...

What is the maximum death rate I should allow?]]>

1: 0.08885 ± 0.00991

2: 0.08744 ± 0.0118

3: 0.10288 ± 0.00669

4: 0.0926 ± 0.01285

My hypothesis is that they are all not significantly different from each other and I would like to put that into a number. Can I run an unpaired t-test putting N=5? I guess I should loose a degree of freedom due to the linear fit. Or are there other tests better...

Significance test comparing slopes from linear fit]]>

To clarify some things - There are 32 cards (4 types), each of the four players get 8 cards for each turn.

The problem is supposed to be solved firstly using combinations and after that using Bernouli scheme, thanks in advance]]>

a) Each group has an equal amount of odd and even numbers,

b) All numbers that are divisible by N, to fall in only one of the groups,

c) All numbers that are divisible by N, to be divided equally in the two groups.]]>

Homer watches Monday Night Football with a probability .6, he has pizza on Monday night with a probability .45, and he does both with probability .25. When you call him on Monday night, you learn that he is watching Monday Night Football. What is the probability that he is having pizza?

The answer is 5/12, I don't understand why

First of all, I do not understand how the probability of doing both is .25. Should it not be .6*.45? So, the formula...

What is the probability that he is having pizza?]]>

In my team, we've gone one better: we have two dates where two people have birthdays on that day!

Trying to work out the probability has us stumped. Not of 4/14 not having unique birthdays, but of two pairs of shared birthdays.

Can someone work me through a solution?

Thanks! Alex]]>

I know that to calculate Pwos (probability of point won on oun serve ) for each player the following formula is used...

# P(no Fault) -The probability a player's first serve not faulting

# P(win/no Fault) -The probability a player will win the point if the first

service does not fault

# P(win/fault) -The probability a player will win the point on his second

serve

formula...

P(win) = P(noFault)P(win/noFault) + (1 -...

Probability of winning a point on serve in tennis]]>

For this problem, assume there are 6 grey females, 2 grey males, 6 white females, and 2 white males. Two mice are randomly selected. What is the probability of selecting two males given that both are grey?

So for selecting two males, I was thinking of 4/12, since there are 4 males in total out of 12. Then for the grey I was thinking of 8/12, since there are 8 grey mice. However, that did not work once I plugged it into the formula...

I...

What is the probability of selecting two males given that both are grey?]]>

Assume for this problem that the company has 8 Chevrolets and 4 Jeeps, and two cars are selected randomly and given to sales representatives.

What is the probability of both cars being Chevrolets, given that both are of the same make?

I have tried many different things, but I do not even understand the question. I am assuming make refers to either a Jeep or a Chevrolet, so for each I am assigning them a Pr of 1/2. The union of both cars...

Conditional Probability and Venn Diagrams]]>

There are 5 history courses of interest to Howard, including 3 in the afternoon, and there are 6 psychology courses, including 4 in the afternoon. Howard picks a course by selecting a dept at random, then selecting a course at random. Find the pr that the course he selects is in the afternoon.

The answer is 19/30, but I get 13/30 by doing this:

For the history dept, the probability of an afternoon class is 1/2 x...

Conditional Probability: Find the probability that the course he selects is in the afternoon.]]>

A. \(\displaystyle \frac{180}{625}\)

B. \(\displaystyle \frac{612}{625}\)

C. \(\displaystyle \frac{216}{625}\)

D. \(\displaystyle \frac{228}{625}\)

E. \(\displaystyle \frac{230}{625}\)

Can someone give me a hint?]]>

How many ways can all the letters in the word ROCKET be arranged so that the vowels are always together?

The answer is 5! x 2.

I understand where the 2 is coming from. What I don't understand is the 5. Shouldn't it be 4!, since we already selected two out of six letters?]]>

An experiment consists of drawing a hand of 5 cards from a standard deck of 52 cards. How many ways can you draw 3 of one suit and 2 of another suit?

I thought it was C(13, 3) x C(13,2). But it turns out it is C(13, 3) x C(13,2) x C(4,2). I don't understand where that last bit comes from. I know there are 4 suits, so I am guessing that bit is choosing two suits out of the four, but...

How many ways can you draw 3 of one suit and 2 of another suit?]]>