Question

Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P,Q and R respectively. What is the proportion of the solution R in the liquid in the tank after 3 minutes?

Answer 1

Answer:

Correct option is

B

11

6

Rate of filling the tank for A:

30

1

Rate of filling the tank for B:

20

1

Rate of filling the tank for C:

10

1

Part filled by (A+B+C) in 3 minutes 3(

30

1

+

20

1

+

10

1

) =(3×

60

11

)=

20

11

.

Part filled by C in 3 minutes =

10

3

.

∴ Required ratio=(

10

3

×

11

20

)=

11

6

.

Answer 2

Answer:

Rate of filling the tank for A:  1/30  

Rate of filling the tank for B: 1/20  

Rate of filling the tank for C:  1/10

Part filled by (A+B+C) in 3 minutes 3 ( 1/30+1/20+1/10)=(3×11/6)=11/20

Part filled by C in 3 minutes = 3/10

requred ratio =(3/10×20/11)=6/11