Question

Find the probability that red crystal marble will be chosen?

Answer 1

Recall that the probability of success is the number of favorable cases over the total number of cases.

From the given data we get that there are 28 red crystal marbles, and there are

`28+36+54+42=160`

marbles in the box, therefore, the probability of choosing a red crystal marble is:

`(28)/(160)=(7)/(40)\text{.}`

Answer: Option B.