Question

A bag contains 100 marbles, some red and some purple. Suppose a student chooses a marble out of the bag, records the color, and then places the marble back in the bag. The students has recorded 9 red marbles and 11 purple marbles.

Using these results, predict the number of red marbles in the bag.

A. 9/100, so 9 marbles
B. 9/20 = 45/100, so 45 marbles
C. 9/11 = 81/99, so 81-82 marbles

Answer 1

B. 45 marbles

Explanation:

9 red + 11 purple = 20

9/20 = 0.45

0.45 x 100 = 45

Answer 2

the predicted number of red marbles in the bag is 45.

Answer: B. 45 marbles.