Question

One pump can empty a pool in 3 days, whereas a second pump can empty the pool in 9 days. How long will it take the two pumps, working together, to empty the pool?It will take the two pumps ___days to empty the pool together.If needed, round answer to 3 decimal places.Enter DNE for Does Not Exist, oo for Infinity

Answer 1

The first pump has a rate of 1/3 a day.

The second pumo has a rate of 1/9 a day.

If both pumps are working together then the total rate is:

$\frac{1}{3}+\frac{1}{9}=\frac{9+3}{27}=\frac{12}{27}$

each day.

Then it will take a total of:

$\frac{27}{12}=2.25$

Therefore it will take the two pumps 2.25 days to emprty the pool together.