Working at constant rate, pump X pumped out half of the water in a flooded basement in 2 hours. The pump Y was started and the two pumps, working independently at their respective constant rates, pumped out rest of the water in 3 hours. How many hours would it have taken pump Y , operating alone at its own constant rate, to pump out all of the water that was pumped out of the basement?
Choices
A) a. 10  B) b. 12  C) c. 14  D) d. 18  E) e. 24
rate of x=1/8   rate of x+y=1/6   rate of y=1/6-1/8=1/24   18 hours   d. 18
<result>D</result>
Working at constant rate, pump X pumped out half of the water in a flooded basement in 2 hours. The pump Y was started and the two pumps, working independently at their respective constant rates, pumped out rest of the water in 3 hours. How many hours would it have taken pump Y , operating alone at its own constant rate, to pump out all of the water that was pumped out of the basement?