How many marbles are in the bowl?

There are 92 marbles in the bowl. These are made up of the twenty red marbles, the 20 x 3 = 60 blue marbles (for we are told that there are three times as many blue and red marbles) and the twelve yellow marbles. 20 + 60 + 12 = 92. so option C is the correct answer.

It is a simple addition problem plus the requirement for the child to take note of the information in the question, a matter that trips up many. S/he than has to multiple 20 x 3 to reach the answer.