Question

A bag contains 50 marbles, 10 of which are blue, 15 are red, 15 are green, and 10 are purple. Shawna takes a marble out of the bag, records the color, and returns it to the bag. How many green marbles should she expect after 200 trials?

30 green marbles
15 green marbles
60 green marbles
100 green marbles

Answer 1

15 out of 50 are green.

Picking a green = 15/50 = 0.3 probability every time.

Multiply the probability by the number of picks:

200 x 0.3 = 60

The answer is 60 green marbles.