Answer
$0.38$ or $38 \% $
Work Step by Step
Recall the basic principle of probabilities:
$P(\text{an event happens})=1-P(\text{an event does not happen})$
In our case, we have the probability of $62 \%=0.62$ that an American owns a pet. Thus, we simply subtract from $1$ to negate this probability:
$P(\text{does not own a pet})=1-P(\text{owns a pet})=1-0.62=0.38$ or $38\%$
