Three pumps can remove a total of 1700 gallons of water per minute from a flooded mineshaft. If engineers want to remove at least 5500 gallons per minute, how many pumps will they need operating?

1 Answer
Jan 11, 2018

color(blue)(10) water pumps

Explanation:

First, write an equation and solve to find how many gallons of water per minute each pump removes:
1700 = 3 * G
G stands for the gallons of water that one pump can remove per minute.
G = 566.bar66 ~~ 566.67 gallons per minute

Then, write an equation and solve to find how many pumps are needed to remove at least 5500 gallons per minute:
5500 = P * G
G = gallons of water per minute per pump
P = number of pumps
5500 <= 566.67P
9.706 = P ~~ 9.71

Since 9.71 pumps would pump 5500 gallons per minute, and you cannot have a fraction of a pump. round up to 10 pumps.

Finally, check your answer:
5500 <= 566.67*10
5500 <= 5666.7