Question

A bag has red, green, and blue marbles. The probability of selecting a red marble is 1/3 and the probability of selecting a green marble is 2/5, what is the probablility of selecting a blue marble

Answer 1

4/15

Explanation:

There are red, green and blue marbles in the bag. The total of all the probabilities of selecting red, green and blue marbles is 1.00, or just 1.

So, to find the probability of selecting a blue marble, we add together 1/3 and 2/5 and subtract the total from 1:

1 - (1/3 + 2/5)

or:

1 - (5/15 + 6/15)

or:

1 - 11/15, or 4/15 (answer)