you own 5 pair of jeans and want to take 2 of them with you on vacation in how many ways can you choose 2 pairs of jeans
A.10 ways
B.15 ways
C.4 ways
D.20 ways
NEED HELP!! DON'T UNDERSTAND!!
5 answers
i got a. 10 ways
Thanks for answer but that doesn't really help me
So, lay out the jeans in a row. There are 5 pairs. Pick the first one. There are 5 ways to do it, right?
That leaves 4 pairs to choose the other one you want. There are 4 ways to pick that one.
So, for each of your first 5 choices, you have 4 other choices, making 5*4 = 20 ways to pick the 2 pairs.
But, picking red,blue is the same as picking blue then red, so we have to divide the total by 2, since the order of choosing does not matter.
That leaves 10, which is 5!/(2!3!)
Better review the material on combinations.
That leaves 4 pairs to choose the other one you want. There are 4 ways to pick that one.
So, for each of your first 5 choices, you have 4 other choices, making 5*4 = 20 ways to pick the 2 pairs.
But, picking red,blue is the same as picking blue then red, so we have to divide the total by 2, since the order of choosing does not matter.
That leaves 10, which is 5!/(2!3!)
Better review the material on combinations.
So, lay out the jeans in a row. There are 5 pairs. Pick the first one. There are 5 ways to do it, right?
That leaves 4 pairs to choose the other one you want. There are 4 ways to pick that one.
So, for each of your first 5 choices, you have 4 other choices, making 5*4 = 20 ways to pick the 2 pairs.
But, picking red,blue is the same as picking blue then red, so we have to divide the total by 2, since the order of choosing does not matter.
That leaves 10, which is 5!/(2!3!)
Better review the material on combinations.
That leaves 4 pairs to choose the other one you want. There are 4 ways to pick that one.
So, for each of your first 5 choices, you have 4 other choices, making 5*4 = 20 ways to pick the 2 pairs.
But, picking red,blue is the same as picking blue then red, so we have to divide the total by 2, since the order of choosing does not matter.
That leaves 10, which is 5!/(2!3!)
Better review the material on combinations.
Yes, that is correct. To choose 2 pairs of jeans out of 5, you can first choose the first pair in 5 ways, and then choose the second pair out of the remaining 4 pairs in 4 ways. However, the order in which you choose the pairs does not matter, so you need to divide by 2 to eliminate the duplicates.
Therefore, the number of ways to choose 2 pairs of jeans out of 5 is:
(5 x 4) / 2 = 10
So the correct answer is A. 10 ways.
Therefore, the number of ways to choose 2 pairs of jeans out of 5 is:
(5 x 4) / 2 = 10
So the correct answer is A. 10 ways.
2 answers