☰ 🔍
🖊️Ask a Question
Electrical Engineering

Two pumps M and N can separately fill a dumper in 36 minutes and 45 minutes respectively. Both the pumps are opened together but 12 minutes after the start the pump M is turned off. How much time will it take to fill the dumper? A) 9 min B) 10 min C) 30 min D) 32 min

by 334 views
Two pumps M and N can separately fill a dumper in 36 minutes and 45 minutes respectively. Both the pumps are opened together but 12 minutes after the start the pump M is turned off. How much time will it take to fill the dumper? A) 9 min B) 10 min C) 30 min D) 32 min
0 like 0 dislike

1 Answer

by
C

12/36 + x/45 = 1

(12*5)/180+4x/180=1

60+4x=180

4x=120

X=120/4=30min
0 like 0 dislike

Related questions

by anonymous asked Jan 10, 2021 11 views
Two pipes, Xand Y can fill a tank in 36 and 30 minutes respectively. Both are opened together, but at the end of 3minutes, X is turned off. In how many more minutes will Y fill the cistern? A) 7(24/5) B) 7(1/2) C) 24(1/3) D) 8(1/4)

Two pipes, Xand Y can fill a tank in 36 and 30 minutes respectively. Both are opened together, but at the end of 3minutes, X is turned off. In how many more minutes will Y fill the cistern? A) 7(24/5) B) 7(1/2) C) 24(1/3) D) 8(1/4) 
Answer : C X can fill cistern in 36 minutes. X fills cistern in 1 minute = 1/36 Y can fill cistern in 30 minutes. Y fills cistern in 1 minute = 1/30 part. Xand Y together can fill cistern in 1 minute, = {(1/ ... part. 147/180 part cistern must be filled by Y in, [(147/180)/(1/30)] = 24(1/3) minutes....

View solution
0 like 0 dislike
1 answer
by anonymous asked Jan 10, 2021 20 views
Three pumps, M, N and O are opened to fill a tank such that M and N can fill the tank alone in 18 min. and 23 min. respectively and O can empty it in 15 min. After 3 minutes the emptying pipe is closed. In how many minutes the tank will be full in this way? A) 20 B) 25 C) 18 D) 12

Three pumps, M, N and O are opened to fill a tank such that M and N can fill the tank alone in 18 min. and 23 min. respectively and O can empty it in 15 min. After 3 minutes the emptying pipe is closed. In how many minutes the tank will be full in this way? A) 20 B) 25 C) 18 D) 12
Answer : D Let the tank full in x minutes, then M and N opened for x minutes and O for 3 minutes. (1/18 + 1/23)*x – (1/15)*3 = 1 (23+18/414)X=1+1/5 Solve, x = 12...

View solution
0 like 0 dislike
1 answer
by anonymous asked Jan 10, 2021 15 views
Two pumps M and N can fill a cistern in 10m and 15m respectively. If both the pumps are opened simultaneously, after how much time should N be closed so that the cistern is full in 8 minutes ? A) 5min B) 6min C) 3min D) 7min

Two pumps M and N can fill a cistern in 10m and 15m respectively. If both the pumps are opened simultaneously, after how much time should N be closed so that the cistern is full in 8 minutes ? A) 5min B) 6min C) 3min D) 7min
Answer :  C X(1/10+1/15) +(8-x)1/10 = 1 5x/30+8-x/10 =1 5x+24-3x/30 =1 2x+24 = 30 2x=6 X=6/2 = 3 ...

View solution
0 like 0 dislike
1 answer
by anonymous asked Jan 10, 2021 23 views
Two taps P and Q can fill a cistern in 24 min and 32 min respectively. Both the taps are opened together for a certain time but due to some obstruction the flow of water was restricted to 7/4 of full flow in tap P and 5/3 of full in tap Q. This obstruction is removed after some time and cistern is now filled in 6min from that moment. How long was it before the full flow. A) 8 min B) 3 min C) 5.6 min D) 4.5 min

Two taps P and Q can fill a cistern in 24 min and 32 min respectively. Both the taps are opened together for a certain time but due to some obstruction the flow of water was restricted to 7/4 of full flow in tap P and ... How long was it before the full flow. A) 8 min B) 3 min C) 5.6 min D) 4.5 min
Answer : D Let the obstruction remain for X min.  Hence, Part of cistern filled in X min + part of cistern filled in 6 min = full cistern [(7X/4*24)+(5X/3*32)]+[(6/24)+(6/32)] = 1 (12X/96)+(7/16) = 1 12x/96=9/16 Thus, X = 4.5 min....

View solution
0 like 0 dislike
1 answer
by anonymous asked Jan 10, 2021 30 views
Taps P, Q and R can fill a tank in 3, 4 and 5 hours respectively. If all the taps are opened together and after 30 minutes taps Q and R are turned off, find the total time in which the tank is full. A) 2(3/8)hrs B) 1(1/7)hrs C) 2(13/40)hrs D) 3(13/43)hrs

Taps P, Q and R can fill a tank in 3, 4 and 5 hours respectively. If all the taps are opened together and after 30 minutes taps Q and R are turned off, find the total time in which the tank is full. A) 2(3/8)hrs B) 1(1/7)hrs C) 2(13/40)hrs D) 3(13/43)hrs
Answer : C In 1 hr P, Q, R = 1/3+1/4+1/5 = 20+15+12/60 = 47/60 Filled in 30m = 47/120 Remaining = 1-47/120 =73/120 Tap P = 3*73/120= 219/120 Total = 219/120+1/2 =219+60 /120= 279/120= 2 13/40 hrs ...

View solution
0 like 0 dislike
1 answer

50.5k questions

47.1k answers

240 comments

7.0k users

© 2025 Question Answer