Rate of Work Done

Tests
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Sample
Rate of Work Done [Test 1]
 1) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 14 hours to empty the tank. Pipe2 takes 16 hours to fill the tank. Pipe3 takes 6 hours to fill the tank. If all three pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)
 2) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 18 hours to fill the tank. Pipe2 takes 11 hours to empty the tank. If both pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)
 3) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 5 hours to empty the tank. Pipe2 takes 8 hours to fill the tank. If both pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)
 4) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 9 hours to fill the tank. Pipe2 takes 9 hours to fill the tank. If both pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)
 5) Jasmine can clean the yard in 14 hours. Mr. B can clean the yard in 1 hour. Jen can clean the yard in 9 hours. If all three of them together clean the yard then how long will it take? hours (Leave the answer as a fraction)
 6) Jasmine can clean the yard in 9 hours. Mr. B can clean the yard in 12 hours. If both of them together clean the yard then how long will it take? hours (Leave the answer as a fraction)
 7) George can paint the wall in 19 hours. Jacob can paint the wall in 7 hours. If both of them together paint the wall then how long will it take? hours (Leave the answer as a fraction)
 8) Val can clean the yard in 17 hours. Jordan can clean the yard in 10 hours. If both of them together clean the yard then how long will it take? hours (Leave the answer as a fraction)
 9) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 4 hours to fill the tank. Pipe2 takes 3 hours to empty the tank. Pipe3 takes 7 hours to fill the tank. If all three pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)
 10) A water tank is connected with several pipes that caries water in and out of the tank. Pipe1 takes 8 hours to fill the tank. Pipe2 takes 4 hours to fill the tank. If both pipes are fully opened then how long will it take to fill the tank? hours (Leave the answer as a fraction)