Abag contains 7 red marbles, 9 blue marbles, and 6 green marbles. what is the probability of choosing a marble that is not green?

Probabilities! In order to find the answer you first have find out the total amount of marbles that you have. So:

[7 + 9 + 6] = 22

This number will go into the denominator. 

The next step is to find how how many marbles are not green. To do that you simply add the red marbles and the blue marbles. So:

[7 + 9] = 16

This number will go in the numerator.

The probability of you choosing a marble that is not green is 16/22. You can also simply this and it would be 8/11.

The answer is part a: use