Question

Doctors use the term maximum heart rate (MHR) when referring to the quantity found
by starting with 220 beats per minute and subtracting 1 beat per minute for each year
of a person’s age. Doctors recommend exercising 3 or 4 times each week for at least
20 minutes with your heart rate increased from its resting heart rate (RHR) to its
training heart rate (THR), where
THR = RHR + .65(MHR – RHR)
Which of the following is closest to the THR of a 43-year-old person whose RHR is
54 beats per minute

Answer 1

A/Q
 MHR = 220 - 1a   , where a = age of guy
so man's MHR = 220 - 43 = 177

and THR = RHR + 0.65(MHR - RHR)

so THR = 54 + 0.65(177-54) = 54 + 0.65(123) = 133.95 beats per minute

hope my ans is correct.