GMATinsight wrote:
Bunuel wrote:
S and T are two water pumps that run at constant rates. If pump T pumped alone, how many more hours would it take for it to finish pumping a large container than it would take for pump S to accomplish the same task by itself?
(1) When both the water pumps work together, they finish pumping a large container in 2/3 rd the time it takes for pump S to finish the task alone.
(2) Pump T is capable of pumping a large container in twice the time that it takes pump S to accomplish the same task alone.
Kudos for a correct solution.
To answer this question, we need to know the relationship between the efficiencies of S and T and the actual amount of time taken by either of them or both of them together to fill the tankStatement 1:When both the water pumps work together, they finish pumping a large container in 2/3 rd the time it takes for pump S to finish the task alone.It gives us the relationship between the efficiencies of S and T but the value of time taken by any one of them or together (in hours) is unknown to arrive at any value of the number of hours
NOT SUFFICIENTStatement 2:Pump T is capable of pumping a large container in twice the time that it takes pump S to accomplish the same task alone.It gives us the relationship between the efficiencies of S and T but the value of time taken by any one of them or together (in hours) is unknown to arrive at any value of the number of hours
NOT SUFFICIENTCombining the two statementsIt gives us the relationship between the efficiencies of S and T but the value of time taken by any one of them or together (in hours) is unknown to arrive at any value of the number of hours
NOT SUFFICIENTAnswer: option E---------------------------------------
I've used the following method, lemme know if this is logically correct:
For S: Rs
For T: Rt
Work: W
Ans will depend on: 1) rate of Rs & Rt
I. Rs+Rt=3W/2Ts
We get the value of Rt in terms of W & Ts (i.e. W/2Ts)
Not giving us a definite answer in terms of the number of hours, hence, NS
II. Ts = 2Ts
This as well isn't giving us a definite answer in terms of number of hours, hence, NS
Therefore, E.
Makes sense?