Question

The average adult heart pumps about 84. mL/s of blood at 72 beats per minute. Suppose you need to calculate how long it would take the average heart tocirculate 6300 mL of blood.Set the math up. But don't do any of it. Just leave your answer as a math expression.Also, be sure your answer includes all the correct unit symbols.

Answer 1

Note that we are told that the average heart pumps 84 mL/s. So, for example after 1 second, the heart would have pumped 84 mL. After one extra second (2 seconds in total) another extra 84 mL would have been pumped. So the total amount of pumped blood after 2 seconds would be

$84+84=2\cdot84$

after another second, we would have another extra 84 mL. So we would have

$84+84+84=3\cdot84$

Note that, in general, after x seconds, the total amount of pumped blood would be

$84\cdot x$

since we are told that the total amount of pumped blood is 6300 mL, we have the following equation

$84\cdot x=6300$

In here, the units would

84 (mL/s) * x (s) = 6300 (mL)

so, if we divide both sides by 84 we have

$x=\frac{6300}{84}$