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#### paulmdrdo

##### Active member

- May 13, 2013

- 386

1. Professors Roberts and james, who live 676 miles apart,

are exchanging houses and jobs for four months. They

start out for their new locations at exactly the same

time, and they meet after 6.5 hours of driving. If their

average speeds differ by 4 miles per hour, what is each

professor’s average speed?

my work is

let $x=$ prof Robert's speed.

$x+4=$ prof. James' speed.

since the took 6.5 hours to meet each other,

i have

$6.5x+6.5(x+4)=676$

$x=50$

$50$ mph - prof Robert's speed

$54$ mph - prof James' speed.

am I correct?

2. Two cyclists start out at the same time from points

that are 395 kilometers apart and travel toward each

other. The first cyclist travels at an average speed of

40 kilometers per hour, and the second travels at an

average speed of 50 kilometers per hour. After how

many hours will they be 35 kilometers apart?

i don't know where to start here.

are exchanging houses and jobs for four months. They

start out for their new locations at exactly the same

time, and they meet after 6.5 hours of driving. If their

average speeds differ by 4 miles per hour, what is each

professor’s average speed?

my work is

let $x=$ prof Robert's speed.

$x+4=$ prof. James' speed.

since the took 6.5 hours to meet each other,

i have

$6.5x+6.5(x+4)=676$

$x=50$

$50$ mph - prof Robert's speed

$54$ mph - prof James' speed.

am I correct?

2. Two cyclists start out at the same time from points

that are 395 kilometers apart and travel toward each

other. The first cyclist travels at an average speed of

40 kilometers per hour, and the second travels at an

average speed of 50 kilometers per hour. After how

many hours will they be 35 kilometers apart?

i don't know where to start here.

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