Paper 1 · November 2021 · Probability
An ice cream vendor's sales are 40% chocolate, 35% vanilla and 25% peach. The probability of a cone sale is 0.80 for chocolate, 0.60 for vanilla and 0.40 for peach. What is the overall probability that a randomly selected sale is by cone?
A0.58
B0.60
C0.63
D0.67
Explanation
By the law of total probability, .
Derived from ZIMSEC Statistics Paper 1, November 2021, Q2