Faucet A basically used as inlet pipe and Faucet B is used as outlet pipe. Faucet A and B both are opened simultaneously, all the time. When Faucet A fills the tank and Faucet B empty the tank, it will take thrice the time than when both the pipes fill the tank. When Faucet B is used for filling the tank, its efficiency remains constant. What is the ratio of efficiency of Faucet A and Faucet B respectively? a) 1:2 b) 2:1 c) 1:3 d) 3:1

1 Answer

Answer :

B

Efficiency when both pipes used to fill = A + B

And efficiency when Faucet A is used to fill and Faucet B is used to empty the tank = A-B

So (A+B)/(A-B)=3/1

A/B+1/(A/B-1)=3/1

A/B+1=3(A/B-1)

3A/B-A/B=4

2A/B=4

A/B=2

Thus, the ratio of efficiency of Faucet A and B =2:1


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