Two pipelines A and B can fill a big tanker in 60 minutes and 40 minutes, respectively. How long will it take to fill the tanker from an empty condition if B fills it half the time and A and B fill it together the other half?
A. 15min
B. 20min
C. 27.5min
D. 30min
Answer:D
Two pipelines A and B can fill a big tanker in 60 minutes and 40 minutes, respectively. How long will it take to fill the tanker from an empty condition if B fills it half the time and A and B fill it together the other half?
A. 15min B. 20min C. 27.5min D. 30min
Explanation: Part filled in 1 minute by (A + B) =1/60+1/40=1/24,Let's say the tank fills up in x minutes.x/2 1/24+1/40 = 1 =x/2 x 1/15 = 1 x = 30 minutes.