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?
a. 197
b. 169
c. 162
d. 134
e. 80