rxs0005
x= { 9 ,10, 11, 12 }
y = { 2,3,4,5}
what is the probability that x / y will be an integer where x is a member chosen from set x and y is a member chosen from set y
1/16
3/8
1/2
3/4
15/16
Personally I think the simplest way to solve this problem would be to just look at the divisibility of numbers individually since it's so few.
This can be done in two ways. Take each term from set x and see which terms in y they are divisible by or vice versa. I'm taking the first approach.
9: 3
10: 2 and 5
11: -
12: 2, 3 and 4.
So the total combinations that are possible where x/y is an integer is the sum of the above expressed combinations and is equal to 6.
The total number of ways of picking two numbers from the sets would be 4C1*4C1 = 16.
So the required probability is \(\frac{6}{16} = \frac{3}{8}.\)
So answer choice B. Hope this helps.
Quote:
Hello, this is my first contribution to the forum (and english is not my mother language) so pardon me if I don't answer in the right way.
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