Question

A bag of candy contains 50 pieces of candy. The flavors are orange, strawberry, apple and

lemon. You know there are 12 orange candies. You pick an orange, put it back because you don'tlike orange and then pick a strawberry. The probability of this happening is 9/125. How many
strawberry candies are there?

Answer 1

15

Explanation:

Let the probability of picking an orange = P(O), and the probability of picking a strawberry = P(S),

Based on the question, he picked an orange first and the probability of picking that is

P(O) = 12/50

Then he picked a strawberry on the second pick, the probability of picking the strawberry is P(S) and we'll find that later.

The probability of picking orange then strawberry with replacement is

P(O) × P(S) = 9/125

Substitute the P(O)=12/50,

12/50 × P(S) = 9/125

P(S) = 3/10

Then by finding the number of strawberry candies, we'll just have to multiply P(S) with the total number of candies, i.e.

Number of strawberry candy

= 3/10 × 50

= 15