If the tank starts with 1000 liters, how much water is left in the tank after 1.5 hours?

Question

Water is pumped out of a holding tank at a rate of 𝑓(𝑡) = 5 − 5𝑒 −0.12t liters per minutes. 't' is in minutes since the pump started. Consider ∫ 𝑓(𝑡) 90 0 𝑑𝑡.

Answer 1

I am not sure you have copied the formula for f(t) correctly, but in 90 min the pump will have pumped out the integral from 0 to 90 of f(t) dt and, of course, the remainder will be 1000-the value of the integral.