Description : 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)
Last 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.
Description : 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
Last 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.
Description : Three pipes P, Q and R can fill a tank from empty to full in 40 minutes, 15 minutes, and 30 minutes respectively. When the tank is empty, all the three pipes are opened. P, Q and R discharge chemical solutions X, Y and Z respectively. ... 5 minutes? a) 8 / 15 b) 7 / 15 c) 8 / 17 d) 6 / 13 e) 8 / 13
Last Answer : a Part of the tank filled by pipe P in 1 minute = 1 / 40 Part of the tank filled by pipe Q in 1 minute = 1 / 15 Part of the tank filled by pipe R in 1 minute = 1/ 30 Here we have to find the proportion of ... together in 5 minute = 5 1/8 = 5/ 8 Required proportion = (1/3) / ( 5/8) = 8 / 15
Description : A large cistern can be filled by 2 pipes P & Q in 120 mins and 80 mins respectively. How many mins will it take to fill the cistern from empty state if Q is used for half the time and P & Q fil it together for the other half? A) 2hrs B) 1hr C) 3hrs D) 4hrs
Last Answer : B Part filled by (P+Q) in 1 min = 1/120 + 1/80 =2+3/240 = 5/240 = 1/48 Suppose the cistern is filled in x mins then, x/2 (1/48 + 1/80) = 1 x/2(5+3/240)=1 8x/480 = 1 x=480/8 x= 60 mins or 1 hr
Description : A cistern is filled in 15 hours by three pipes P, Q and R. The pipe R is thrice as fast as Q and Q is thrice as fast as P. How much time will pipe P alone take to fill the tank? A) 120 hrs B) 195 hrs C) 135 hrs D) Cannot be determined
Last Answer : B Suppose pipe P alone takes x hours to fill the tank. Then, pipes Q and R will take x/3 and x/9hours respectively to fill the tank. 1/x + 3/x + 9/x = 1/15 13/x = 1/15 => x = 195 hrs.
Description : Pipes P, Q and R which fill the tank together in 12 hours are opened for 2hours after which pipe R was closed. Find the number of hours taken by pipe R to fill the tank if the remaining tank is filled in 14 hours. A) 16 B) 14 C) 20 D) 42
Last Answer : D 1/P + 1/Q + 1/R = 1/12 Now given that first all open for 2hours, then R closed and P+Q completes in 14 hours, so (1/P + 1/Q + 1/R) *2 + (1/P + 1/Q)*14 = 1 Put 1/P + 1/Q = 1/12 – 1/R (1/12 – 1/R + 1/R) *2 + (1/12 – 1/R)*14 = 1 1/6+ 14/12 – 14/R = 1 Solve, R = 42
Description : A tank is 1/4th full. Two pipes which fill the tank in 30minutes and 40 minutes respectively are opened simultaneously. After 10 minutes, a third pipe which empties the full tank in 60 minutes is also opened. In how many minutes the tank will be full? A) 14 B) 12 C) 15 D) 17
Last Answer : A Since 1/4th is already filled, 3/4th is to filled now. (1/30 + 1/40)*(10+x) – (1/60)*x = ¾ 7/120(10+x)-x/60=3/4 7x-2x/120=3/4-7/12 5x/120=1/6 30x=120 X=4 So total 10+4=14minutes
Description : Two pipes can fill a tank in 20 and 24 minutes respectively and another pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank in gallons is: a)100 b)110 c)120 d)140
Last Answer : c)120
Description : A tank can be filled by a tap in 6 hours and emptied by an outlet pipe in 8 hours. How long will it take to fill the cistern if both the taps are opened together? 1. 24 hours 2. 22 hours 3. 21 hours 4. 18 hours 5. 20 hours
Last Answer : 1;
Description : two pipes X and Y can fill a cistern in 18 hrs and 24 hrs respectively. If both the pumps are opened simultaneously. How much time will be taken to fill the cistern? A) 10hrs 50mints B) 10 hrs 5mints C) 10hrs 17mints D) 10hrs 44mints
Last Answer : C Part filled by x in 1hour = 1/18 Part filled by y in 1 hour = 1/24 Part filled by (x+y) in 1 hour = 1/18 + 1/24 =>4+3/72 =>7/72 The cistern will be full in 72/7 hrs = 10 hrs 17mins.
Description : Two pipe P & Q fill a tab in 5 hrs and 20 hrs respectively. If both the pipes are open then due to the leakage, it took 30mins more to fill the tab. If the tab is full, how long will it take for the leakage alone to empty the tank? A) 28 B) 24 C) 36 D) 12
Last Answer : C Part filled by(P+Q) in 1 hr = 1/5 + 1/20 = ¼ So P & Q together can fill the tank in 4 hrs. Work done by the leak in 1 hr = 1 / 4 - 2/9 Leak will empty the tank in 36 hrs.
Description : 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
Last 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
Description : 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
Last 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
Description : Two pumps P & Q can fill a tank in 12 mins and 15 mins respectively while a third pipe R can empty the full tank in 6 mins. P & Q kept open for 5 mins in the beginning and then R is also opened. In what time is tank emptied? A) 30mins B) 35mins C) 40mins D) 45 mins
Last Answer : D Part filled in 5 min = 5(1/12 +1/15) = 5*9/60 = ¾ Part emptied in 1 min when all the pumps are opened, = 1/6 – (1/12 + 1/15) = 1/6 – 3/20 = 1/60 Now 1/60 is part emptied in 1 min Therefore ¾ part will be emptied in 60 * ¾ = 45 mins
Description : 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
Last 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
Description : Four pipes can fill a reservoir in 15, 20, 30 and 60 hours respectively. The first one was opened at 6 AM, second at 7 AM, thir da t 8 AM and the fourth at 9 AM. When will the reservoir be filled ? (A) 11 AM (B) 12 Noon (C) 1 PM (D) 1:30 PM
Last Answer : Answer: C
Description : Two tube A and B can fill a cistern in 48 mins and 64 mins. If both the tubes are opened simultaneously, after how much time B should be closed so that the cistern is full in 36 minutes? A) 20 mins B) 16mins C) 22mins D) 14mins
Last Answer : B Let B be closed after ‘x’ mins. Then part filled by (A+B) in x mins + part filled by A in (36 – x) mins = 1 Therefore x(1/48 + 1/64) + (36 – x)* 1/48 = 1 7x/192 + 36 – x/48 = 1 7x + 4(36-x)/192 = 1 7x+144 – 4x = 192 3x = 48 =>x = 16 Here B must be closed after 16 mins.
Description : 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 ... efficiency of Faucet A and Faucet B respectively? a) 1:2 b) 2:1 c) 1:3 d) 3:1
Last 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
Description : 3 faucet P,Q & R can fill a cistern in 12 hrs. After working together for 4hrs, R is closed P and Q can fill the remaining part in 14 hrs. The number of hrs taken by R alone to fill the cistern is. A) 18 hrs B) 20 hrs C) 28hrs D) 30hrs
Last Answer : C Part filled in 4 hrs = 4/12 = 1/3 Remaining part = 2/3 (P+Q)’s 14 hrs work = 2/3 (P+Q)’s 1 hr work = 2/ 3 *14 = 1/21 R’s 1 hr work = (P+Q+R)’s 1 hr work – (P+Q)’s 1 hr work = 1/12 – 1/21 = 7-4/84 = 3/84 = 1/28 R alone can fill the tank in 28 hrs.
Description : Two taps P and Q can separately fill a tank in 120mins and 150 mins respectively. There is a 3rd tap in the bottom of the tank to empty it. If all of the 3 taps are simultaneously opened, then the tank is full ... . In how much time the 3rd pipe alone can empty the tank? A) 100 B) 200 C) 300 D) 400
Last Answer : B Work done by the 3 tap in 1 min = 1/100 – ( 1/120 + 1/150) = 1/100 – (5+4/600) =1/100 – 9/600 =6-9/600 = - 3/600 = - 1/200(negative signs mean empting) Therefore the 3rd tap alone can empty the tank in 200 mins
Description : Two faucet can separately fill a cistern 30minutes and 45 minutes respectively and when the waste faucet is open, they can together fill it in 54 minutes. The waste faucet can empty the full cistern in? A) 27 min B) 23 min C) 23 min D) 29 min
Last Answer : A 1/30 + 1/45 - 1/x = 1/54 1/x=1/30+1/45-1/54 1/x=9+6-5/270 1/x=10/270 1/x=1/27 x = 27
Description : Two pipes A and B can fill a tank in 5 and 6hrs.Pipe C can empty it in 12hrs.If all the 3 pipes are opened together,then the tank will be filled in 1)1(13/17)hrs 2)2(8/11)hours. 3)3(9/17)hrs 4)4(1/2)hrs
Last Answer : 3)3(9/17)hrs Exp:Net part filled in 1hr=>(1/5+1/6-1/12)=17/60 Tank filled in=60/17=3(9/17).
Description : Pipe A can fill a water tank in 8 hours, Pipe B can fill the same tank in 12 hours and Pipe C can empty the tank in 24 hours. If all three pipes are opened together, in how many hours will the tank be completely filled or empty? a) 4.8 hours b) 5 hours c) 5.4 hours d) 6 hours e) 7.2 hours
Last Answer : If all the three pipes are opened together, in one hour they will fill 1/8 + 1/12 – 1/24 = (3+2-1)/24 = 1/6 part of tank. So, to fill it completely it will take 6 hours. Answer is: d)
Description : Two faucet p and q can fill a tank in 10 minutes and 20 minutes.If both faucet are opened simultaneously , after how much time should q be closed so that the tank is full in 9 minutes ? A) 2 min B) 9 min C) 4 min D) 7min
Last Answer : A p fill the tank in 1 minute (10×2 = 20) = 2 units q fill the tank in 1 minute (20×1 = 20) = 1units For 9 min(p) = 9×2 = 18 units Remaining = 20 – 18 = 2 units Time for q be closed so that the tank is full in 9 minutes = 2/1 = 2 min
Description : Two faucet A and Bcan fill a cistern in 6 hours and 2 hours respectively. If they are opened on alternate hours and if faucet A is opened first, in how many hours will the cistern be full? A) 4 hours B) 5 hours C) 7 hours D) 6 hours
Last Answer : A Faucet A can fill = 1/6 faucet B can fill = 1/2 For every two hour, 1/6 + 1/2 = 1+3/6 =>4/6=2/3 Part filled Total filled in 3 hours = 2/3+1/6= 5/6 In next hour it will be fille full. So total time will be 4 hours.
Description : 3 faucet A,B,C can fill a cistern from empty to full in 45mins, 35mins, and 25 mins respectively. When the cistern is empty all the 3 faucets are opened. A,B,c discharge chemical solutions A,B,C respectively. What is ... the liquid in the tank after 5 mins? A) 63/143 B) 72/151 c) 67/173 D) 81/167
Last Answer : A Part filled by (A+B+C) in 5 mins = 5(1/45 +1/35 + 1/25) = 5 (35+45+63/1575) = 143/315 Part filled by c in 5 mins = 5/25 = 1/5 Required ratio = 1/5 * 315/143 =63/143.
Description : 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
Last Answer : C 12/36 + x/45 = 1 (12*5)/180+4x/180=1 60+4x=180 4x=120 X=120/4=30min
Description : Three pipes, A, B, & C are attached to a tank. A & B can fill it in 20 & 30 minutes respectively while C can empty it in 15 minutes. If A, B & C are kept open successively for 1 minute each, how soon will the tank be filled?
Last Answer : Answer: 167 minutes.
Description : Two faucet P and Q can fill a tank in 10 min. and 20 min. respectively. A water faucet R can empty the tank in 10 min. First P and Q are opened. After 3 min, R is also opened. In how much time, the tank is full? A) 17m B) 15m C) 11m D) 19m
Last Answer : C Part filled in 3 min. = 3*((1/10)+(1/20)) = 3 * (2+1/20) =>3(3/20) = 9/20 Remaining part=(1-(9/20))=(11/20). Net part filled in 1min. when P,Q and R are opened=(1/10)+(1/ ... (1/20). Now,(1/20) part is filled in one minute. (11/20) part is filled in = (20*(11/20))=11minutes.
Description : A tube can fill a cistern in 18hrs.After half the cistern is filled, three more similar tubes are opened. What is the total time taken to fill the cistern completely ? A) 9hrs 52min B) 10hrs 15 min C) 9hrs 45 min D) 10hrs 30min
Last Answer : Time taken to fill half of the cistern = 18/2 = 9 hrs After half the cistern is filled , three more similar tubes are opened. We know that one tube can in 18 hrs can fill = V litres(i.e. fully fill a cistern) ... V/2 will be 2 hrs 15 min Total time = 9 hrs + 2 hrs + 15 min = 11 hrs 15 min
Description : A pipe can fill a tank in 4 hours and another pipe can empty the same tank in 6 hours. When both the pipes are opened simultaneously, the part of tank
Last Answer : A pipe can fill a tank in 4 hours and another pipe can empty the same tank in 6 hours. When both the ... the part of tank filled in 1 hour is ..
Description : A pump can fill a cistern in 12 hrs. After half the cistern is filled, 3 more similar pumps are opened. What is the total time taken to fill the cistern completely? A) 8 hrs B) 4 hrs C) 2hrs D) 7.5 hrs
Last Answer : D Time taken by 1 pump to fill tha half tank = 6 hrs Part filled by the 4 pumps in 1 hr = 4 * 1/12 =1/12 =>1/3 Remaining part = (1 – 1/2)= 1/2 Therefore 1/3 :1/2 :: 1:x X=1.5 hrs So total time takem = 6hrs + 1.5 hrs = 7.5 hrs.
Description : Two pipes X and Y can fill a tank in 6 hours and 8 hours respectively while another pipe Z can empty the tank in 4.8 hours. If all the three pipes are
Last Answer : Two pipes X and Y can fill a tank in 6 hours and 8 hours respectively while another pipe Z can ... then the time in which the tank can be filled.
Description : Two taps A and B are opened together to fill a tank. Both the taps fill the tank in time x If B separately took 25 minutes more time than x to fill the tank and B took 49 minutes more time than x ... the tank, then find out the value of x? A) 48 minutes B) 24 minutes C) 54 minutes D) 35 minutes
Last Answer : D Time is taken to fill the tank by both taps x = √a*b x = √25*49 => 5*7 => 35
Description : Pipe A can fill an empty tank in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins. If all of them work together, find the time taken to fill the tank? (a) 17 1/7 mins (b) 20 mins (c) 8 mins (d) none of these
Last Answer : (a) 17 1/7 mins
Description : Two faucet A and B can fill a tank in 20 hours and 40 hours respectively. If they are opened simultaneously. Sometimes later, tap B was closed, then it takes total 14 hours to fill up the whole tank. After how many hours B was closed? A) 4 hours B) 15.2 hours C) 12 hours D) 17.6 hours
Last Answer : A Let x is the time when B is closed X(1/20+1/40)+14/20=1 X=4 hours
Description : One tap can fill a cistern four times as fast as another tap. If together the two taps can fill the cistern in 48 mins then the slower tap alone will be able to fill the cisterns. A) 1hr B) 2hr C) 3hr D) 4hr
Last Answer : D Let the slower tap alone fill the cistern in x mins Then faster tap will fill it in x/4 mins Therefore 1/x +4/x = 1/48 5/x = 1/48 X = 48*5 x = 240 mins x = 4 hrs.
Description : A water cistern is two-fifth full. Tap A can fill a cistern in 20 mins and tap B can empty it in 12mins. If both the taps are open, how long will take to empty or fill the cistern completey? A) 10 mins B) 12mins C) 14mins D) 16 mins
Last Answer : B Clearly tap B is faster than the Tap A and so, the cistern will be emptied Part to be emptied = 2/5 Part emptied by (A+B) in 1 min = (1/12 – 1/20) = 5-3/60 = 2/60 =>1/30 Therefore 1/30 : 2/5 :: 1;x x= 1*2/5 *30/1 = 12mins so the tank will be emptied in 12mins.
Description : A tank has two faucet which fill it in 15 mins and 18 mins respectively. There is also a waste faucet in the tank. When all the 3 are opened the empty tank is full in 25 mins. How long the waste faucet take to empty the full tank? A) 450/17 mins B) 450/28 mins C) 450/37 mins D) 450/22 mins
Last Answer : C Work done by the waste faucet in 1 minute =>1/25 – (1/15 + 1/18) =>1/25 – (6+5/90) = 1/25 – 11/90 => - 37/450 Here negative sign means emptying Therefore waste faucet will empty the full tank in 450/37 mins.
Description : Two pipes fills a tank in 12 hours and 15 hours respectively while a third pipe empties the tank in 18 hours. !f all three pipes operate simultaneously, in what time will the tank be full? a) 10 hours b) 10 10/17 hours c) 11 hours d) 9 hours e) 12 1/17 hours
Last Answer : b) 10 10/17 hours
Description : Two filling tap can fill a dumper in 14 and 28 min. respectively and when the waste tap is open, they can together fill it in 35 min. The waste pipe can empty the full dumper in – A) 152/9 hrs. B) 137/7 hrs. C) 60/9 hrs. D) 140/11 hrs.
Last Answer : D 1/14 + 1/28 – 1/35 =>10 + 5 – 4/140 =>11/140 =>140/11 => hence answer is 140/11 hours.
Description : A cistern is filled by three faucets with uniform flow. The first two faucets operating simultaneously fill the cistern in the same during which the cistern is filled by the third faucet alone. The second faucet fills the cistern ... by the first faucet is? A) 6 hrs B) 10 hrs C) 15 hrs D) 30 hrs
Last Answer : C Suppose, first faucet alone takes x hours to fill the cistern. Then, second and third faucets will take (x - 5) and (x - 9) hours respectively to fill the cistern. 1/x + 1/(x - 5) = 1/(x - 9) (2x - 5)(x - 9) = x(x - 5) x2 - 18x + 45 = 0 (x- 15)(x - 3) = 0 => x = 15
Description : Three pipes A, B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is: a) 10 b) 14 c) 12 d) 13 e) 15
Last Answer : (A+B+C) - (A+B) (A+B+C) =1/6 and (A+B+C) in 2hrs=2/6 and remaining part 1-2/6=2/3. So (A+B) in 7 hrs is 2/ (3*7) =2/21. 1/6-2/21=1/14 so answer is 14. Answer: b)
Description : Three friends started a Company, let there names are P, Qand R. What profit Q will get, if, 1. R invested Rs. 4000 for nine months, his profit was 3/2 times that of Q's and his investment was four times that of P. 2. ... year end. A) Only 1 and 3 B) Only 1 and 2 C) All 1, 2 and 3 D) None of above
Last Answer : Answer: C) 1 and 2 will give : R = Rs. (4000 x 9) for 1 year = Rs. 36000 for 1 year. P = Rs. (1/4 * 4000 * 12 ) for 1 year = Rs 12000 for 1 year Q = Rs 24000 for one year R:P:Q = ... Profit = 500 Now from the ratio and total profit we can get Share of R. R share will be = 500 * 2/6 = 166.66
Description : A tank can be filled by a tap in 8 hrs while it can be emptied by another tap in 18 hrs. if both the taps are opened simultaneously, then after how much time will the cistern get filled? A) 14hrs 24mins B) 14 hrs 12 mins C) 14hrs 56 mins D) 14hrs 30mins
Last Answer : A Net part filled in 1hr = (1/8 – 1/18) = 9 – 4/72 = 5/72 Therefore the tank will be filled in 72/5 hrs i.e., 14 hrs 24mins
Description : A cistern can be filled in 25 minutes. There is a leakage which can empty it in 50 minutes. In how many minutes cistern can be filled? a) 20 mints b) 25mints c) 45 mints d) 50 mints
Last Answer : D Efficiency of filling faucet= 100/25 = 4% ⇒ Efficiency of leakage faucet = 100/50= 2% ⇒ Net filling efficiency = (4-2)% =2% So, t cistern can be filled in = 100/2 = 50 minutes
Description : Two pipes X and Y can fill a bunker in 24 hours. If only pipe X is open then it would take 12 hours longer to fill the bunker. Find how much longer would it take if only pipe Y is open. A) 46hrs B) 32hrs C) 48hrs D) 34hrs
Last Answer : C X= 24+12 = 36 X+Y= 1/24 Y= 1/24 – 1/36 = 3-2/72 = 1/72 Y= 72 X alone= 72-24 = 48 HRS
Description : A tap can fill a cistern in 11hours, but due to a leakage it took 13hours to fill the cistern. If the cistern is full, in what time will the cistern become empty due to leakage ? A) 73.30hrs B) 77.50hrs C) 71.5 hrs D) 72.30hrs E) None of these
Last Answer : C 1/11-1/13 = 13-11/143 =>2/143 =>1/71.5 =>71.5hours
Description : A tank has two inlet pipes, A and B, which can fill the tank in 12 hours and 18 hours respectively, and an outlet C which can empty the tank in 9 hour
Last Answer : A tank has two inlet pipes, A and B, which can fill the tank in 12 hours and 18 hours ... time taken right from the start to fill the tank.
Description : Three taps P,Q,R can fill a bunker in 3 hrs. After working at it together for 1 hr, R is closed and P,Q can fill the remaining part in 3 hrs. The number of hrs taken by R alone to fill the bunker. A) 9hrs B) 7hrs C) 11hrs D) 5hrs
Last Answer : A Part filled in 1 hr = 1/3 Remaining part = 1 – 1/3 = 2/3 (P + Q)’s 3 hours work = 2/3 (P+Q)’s 1 hour work = 2/9 R’s 1 hr work = [(P+Q+R)’s 1 hr work – (P+Q)’s 1 hr work] = 1/3 – 2/9 = 3-2/9 = 1/9 R alone can fill the tank in 9 hours.