A city water tank holds 20 gallons of water. A technician empties 25% of the tank. How many more gallons of water must be removed from the tank so that it has 2/5 of the water that it started with?
The technician must remove (ANSWER)
more gallons of water for the tank to have 2/5 of the water that it started with.
There is 100% in any full thing. When the water tank was full, it had 20 gallons. After 25% of the water was removed, there is 75% left (100% - 25% = 75%). 75% can also equal 0.75. 20 × 0.75 = 15 gallons.
