- #1
nille40
- 34
- 0
Hi all!
In how many unique ways can 4 dices be combined? Note that the order amongst the dices is not relevant, so 1-2-3-4 = 4-3-2-1.
My idea is that you select the values, one by one. You can select the first value in 6 ways, the second in 6 ways, the third in 6 ways and the fourth in 6 ways. This yield [tex]6^4[/tex] combinations. The order was irrelevant, so the answer should then be [tex]\frac{6^4}{4!}[/tex].
This is obviously wrong... I'm trying to figure out how to think to solve a problem like this.
The answer is
[tex]{6+4-1} \choose {4}[/tex]
Which basically means "select 4 of the 6, and put each value back when you've selected it". I don't get this...
Would really appreciate some guidance!
Nille
In how many unique ways can 4 dices be combined? Note that the order amongst the dices is not relevant, so 1-2-3-4 = 4-3-2-1.
My idea is that you select the values, one by one. You can select the first value in 6 ways, the second in 6 ways, the third in 6 ways and the fourth in 6 ways. This yield [tex]6^4[/tex] combinations. The order was irrelevant, so the answer should then be [tex]\frac{6^4}{4!}[/tex].
This is obviously wrong... I'm trying to figure out how to think to solve a problem like this.
The answer is
[tex]{6+4-1} \choose {4}[/tex]
Which basically means "select 4 of the 6, and put each value back when you've selected it". I don't get this...
Would really appreciate some guidance!
Nille