# 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?

Jan 11, 2018

$\textcolor{b l u e}{10}$ water pumps

#### Explanation:

First, write an equation and solve to find how many gallons of water per minute each pump removes:
$1700 = 3 \cdot G$
G stands for the gallons of water that one pump can remove per minute.
$G = 566. \overline{66} \approx 566.67$ gallons per minute

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

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

$5500 \le 566.67 \cdot 10$
$5500 \le 5666.7$