Answer :
If all the flushes were full flushes: 1190 + 3150 = 4340 full flushes in total. Because the full flush uses 1.6 gallons, multiply 4340 and you get 6944 gallons of water used per week before the partial flushes were installed.
(1190 full flushes * 1.6 gallons) + (3150 partial flushes * 0.9 gallons) = 4739 gallons used.
Subtract 4739 gallons from 6944 gallons to get the amount of gallons saved for the week, which is 2205 gallons.
(1190 full flushes * 1.6 gallons) + (3150 partial flushes * 0.9 gallons) = 4739 gallons used.
Subtract 4739 gallons from 6944 gallons to get the amount of gallons saved for the week, which is 2205 gallons.