The theoretical probability is defined as the ratio of the number of favourable outcomes to the number of possible outcomes.
Conditional probability is defined as the likelihood of an event or outcome occurring, based on the occurrence of a previous event or outcome.
The desired probability on the problem is
The probability that a person do not exercise given it is a male. This probability is given by the ratio between the male that don't exercise by the total amount of males.
Our probability is 18%.