Question

Jason and Kyle both choose a number from 1 to 10 at random. What is the probability that both numbers are odd?

Answer 1

There are ten numbers between 1 and 10 , and
five of them are odd.

The probability that Jason will choose an odd number is

5/10 = 1/2 = 0.5 = 50% .

The probability that Kyle will choose an odd number is

5/10 = 1/2 = 0.5 = 50% .

The probability that BOTH events will happen is

(1/2)² = 1/4 = 0.25 = 25% .

Answer 2

First figure out how many numbers from 1 to 10 are odd. The odd numbers would be: 1, 3, 5, 7, and 9. So we know that there are 5 odd numbers between 1 and 10.

Therefore, the chance that one of them chooses an odd number is 5/10 (5 odd numbers out of 10 total numbers), or simplified to 1/2.

The chance of BOTH of them choosing an odd number is found by multiplying the chance of one of them choosing an odd number times the chance of the other choosing an odd number:

1/2 x 1/2 = 1/4

Therefore the chance of both of them choosing an odd number is 1/4, or 25%