Question

Tank B, which initially contained 80 liters of water, is being drained at a rate of 2.5 liters per minute. For how many minutes has the water been draining when Tank B contains 75 liters of water?

Answer 1

We get that the function that models this situation is

`L=80-2.5m`

where L is the liters the tank contains and m is the minutes that has passed. So we get:

`75=80-2.5m\rightarrow m=(-80+75)/(-2.5)=2`

so the tank has been drained for 2 minutes