Real-Life Math
You're a cardiovascular surgeon giving a noon-hour lecture to
university students, telling them about ways to have a healthier heart. You
say that eating a nutritious diet, quitting smoking and being active can go
a long way to helping them have a healthy heart.
A student raises her
hand and asks how she can tell if she's exercising hard enough to benefit
her heart health. This is what you tell her:
To calculate
your resting heart rate, press lightly with your index finger on your carotid
or your radial artery. Your carotid artery is located beneath your jawbone,
beside your Adam's apple. The radial artery is on the inside (on the thumb
side) of your wrist.
Press lightly and count your heartbeat for 10 seconds.
When you've finished, multiply this number by 6. By calculating your
resting heart rate, you then have a benchmark for figuring out what level
you should raise your heart rate to when you're exercising.
"There
is not a lot of math used daily," says Dr. Tea Acuff, a cardiovascular surgeon.
"Basic algebra skills are used from time to time."
However, to become
a cardiovascular surgeon, high school students must study mathematics. "If
you don't go for all the math you can in high school, you won't
get this far."
Questions:
- John presses his finger to his radial artery and in 10 seconds counts
12 beats. What is his resting heart rate in beats per minute?
- April presses her finger to her carotid artery and counts 20 beats. That
sounds a bit high, but when she looks at her stopwatch, she finds she has
counted for 15 seconds. What is her resting heart rate in beats per minute?
- Roger presses his finger to his radial artery. He's too impatient
to wait for 10 seconds. In 5 seconds, he counts 7 beats. What is his resting
heart rate in beats per minute?