Question

There is a bag with only red marbles and blue marbles.

The probability of randomly choosing a blue marble is
11/12
There are 72 marbles in total in the bag and each is equally likely to be chosen.
Work out how many red marbles there must be.

Answer 1

6

Explanation:

The no of blue marble= 72 x 11/12 =66

72-66=6

Answer 2

• 6 red marbles

Explanation:

11/12 = 66/72

66 blue marbles out of 72

Red marbles = 72 - 66 = 6