Question

Whilst shopping, the probability that Caroline buys fruit is 0.6.
The probability that Caroline buys a CD is 0.2.
Buying fruit and buying a CD are independent of each other.
Work out the probability that she buys fruit, a CD or both

Answer 1

Probability of buying fruit $P(f)=0.6$

Probability of buying a CD $P(c)=0.2$

Since the two actions are independent,

Probability of buying both $P(fc)=P(f)×P(c)$

Thus, $P(fc)=0.6×0.2=0.12$

Probability of buying fruit, a CD or both is $P(f)+P(c)-P(fc)$ $=0.6+0.2-0.12=0.68$

Answer: 0.68.