Evaluate 3b-2a-9 a= 1/2 and b=7

Apair of ordinary dice is rolled. what is the probability that each die will show a number higher than 4. 1. (1/36) 2. (1/12) 3. (1/6) 4. (1/4) 5. (1/3)

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

How much would it be worth in 5, 10, 20 years