Question

A cereal company is putting 1 11 of 4 44 prizes in each box of cereal. The prizes are evenly distributed so the probability of winning any given prize is always 1 / 4 1/41, slash, 4.

Answer 1

0.75

Explanation:

The complete question is attached below.

The dots on the numbers of the dot plot represent the number of boxes it took Vera to get all the prizes.

Therefore, the probability of getting all the prizes in 9 or fewer boxes is the sum of the number of times it took her to get 4 prizes in 9 boxes or fewer.

Hence:

P(x ≤ 9) = P(x = 4) + P(x = 5) + P(x = 6) + P(x = 7) + P(x = 8) + P(x =9)

P(x ≤ 9) = (4 / 36) + (6 / 36) + (3 / 36) + (4 / 36) + (4 / 36) + (6 / 36)

P(x ≤ 9) = 27 / 36

P(x ≤ 9) = 3 / 4 = 0.75