D I did this question a while back
Answer:
It is a 1/3 chance that he will pick size 8.
Step-by-step explanation:
I know that there are 3 sizes, and only one of the sizes is 8, so 1 out of the 3 pairs, or 1/3.
It would be -2x+3x=2, you combine like terms and divide. your answer should be 2, hope this helps