The target heart rate for moderate exercise is $50\%$ to $70\%$ of maximum heart rate. We can use the expression $\frac{p}{100}(220-a)$ to represent a person’s target heart rate when their target rate is $p\%$ of their maximum heart rate, and they are $a$ years old.
Determine the target heart rate at the $53\%$ level for moderate exercise for someone who is $56$ years old.
At the $53\%$ level, the target heart rate for moderate exercise for someone who is $56$ years old is beats per minute.