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

1 Answer

Answer :

(a) 17 1/7 mins
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Related questions

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 : 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 : 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 : 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 : 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 : 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 : Pipe A usually fills a tank in 2 hours. On account of a leak at the bottom of the tank, it takes pipe A 30 more minutes to fill the tank. How long will the leak take to empty a full tank if pipe A is shut? a) 4 hours b) 3 hours c) 6 hours d) 8 hours e) 10 hours

Last Answer : portion of the tank filled by the pipe A in 1 hour = ½ of the tank let the portion of the tank emptied because of the leak in 1 hour be 1/x of the tank therefore, in 1 hour , portion of the tank filled = 1/2 - 1 ... 1/2 - 1/x = 1/2.5 or x = 10 hence, it takes 10 hours to empty a full tank Answer: e)

Description : Two taps can fill a bunker in 40 and 48 mins respectively and a waste tap can empty 6 gallons per minute. All the 3 taps working together can fill the bunker in 30 mind. The capacity of the bunker is. A) 480 B) 480 C) 680 D) 780 

Last Answer : A Work done by the waste tap in 1 min = 1/30 – (1/40 + 1/48) = 8 – (6+5)/240 = 8-11/240 = -3/240 = -1/80 (negative sign means emptying) Volume of 1/80 part = 60 gallons Volume of whole = (6*80) = 480 gallons

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 : 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 : 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 : 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 : 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 : A barrier has four inlets A, B, C and D. The barrier can be filled in 24 minutes through the first three inlets and it can be filled in 30 minutes through the second, the third and fourth inlet also it can be ... all the four inlets? A) 10 mins B) 15 mins C) 20 mins D) 25 mins E) None of the Above

Last Answer : C (1/A + 1/B + 1/C) = 1/24 …(i) (1/B + 1/C + 1/D) = 1/30 …(ii) (1/A + 1/D) = 1/40…(iii) From eqn (i) and (ii) (1/A – 1/D) = 1/120…(iv) From eqn (iii) and (iv) A=60,D=120. Let the time taken to full the tank = s S(1/A + 1/B +1/C +1/D)= 1 S(1/24+1/120) = 1 S= 20 mins

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 : 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 : 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 : 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 : Two tap can fill a dumper in 7 hrs and 8 hrs respectively. The taps are opened simultaneously and it is found that due to leakage in the bottom it took 16 mins more to fill the dumper. When the dumper is full, in what time will the leak empty it? A) 56hrs B) 56hrs C) 46hrs D) 36hrs

Last Answer : A Work done by 2 taps in 1 hr = (1/7 + 1/8) = 15/56 Time taken by these taps to fill the dumper = 56/15 hrs =3 hrs 44 mins Due to leakage, time taken = 3 hrs +44mins+16 mins =4hrs Work done by (2 ... the leak in 1 hr = (15/56 - ¼) =15 - 4/56 =1/56 Leak will empty the full cistern in 56 hrs.

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 : 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 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 : 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 : 24 pumps are connected to a tank. Some of them are inlet pumps and the others are outlet pumps. Each of the inlet pumps an fill the tank in 16hours and each of the outlet pumps can empty the tank completely in ... gets filled in 48 hours. How many inlet pumps are there? A) 16 B) 18 C) 17 D) 14

Last Answer : D (x/16)-[(24-x)/12] = 1/48 x/16-24/48+x/12=1/48 (3+4)x/48=97/48 7x/48=97/48 7x=97 X=14

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 : 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 : 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 : A pipe can fill the tank in 12 hours.Because of a leak in the tank it took 16(1/2) hours to fill the tank.If the tank is full,how much time will the leak take to empty it? A) 18hrs51mins B) 18hrs 20min C) 18hrs 40min D) 18hrs 45min E) None of these

Last Answer : A =>1/12-2/33 = 11-4/132. ==>7/132 =>132/7 hrs =>132/7 hrs=>1131 mins =>18hrs 51min

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 : Two pipes P and Q can fill a cistern in 15 minutes and 20 minutes respectively. Both are opened together, but at the end of 5 minutes, the pipe P is t

Last Answer : Two pipes P and Q can fill a cistern in 15 minutes and 20 minutes respectively. Both are opened ... will the pipe Q take to fill the cistern ?

Description : Two taps M and N can alone fill a tank in 80 minutes and 120 minutes respectively. But due to a leakage of tank, it took 12 more minutes to fill the tank. In how many hours, the leak can alone empty the full tank? A) 240 B) 230 C) 248 D) 256

Last Answer : A A and B can fill tank in (1/80 + 1/120) = 1/48 so 48minutes But it took 12 more minutes, this means the tank got full in 48+12= 60 minutes So (1/80 + 1/120 – 1/x) = 1/60 1/X=1/80+1/120-1/60 Solve, x = 240

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 : Thirty men take 20 days to complete a job working 9 hours a day. How many hour a day should 40 men work to complete the job? (a) 8 hrs (b) 7 1/2 hrs (c) 7 hrs (d) 9 hrs

Last Answer : (b) 7 1/2 hrs

Description : A girl covered a definite distance at same speed. Had she moved 6 km/hr faster, she would have taken 30 mins less. If she had moved 4 km/hr slower, she would have taken 30 mins more. The distance (in km) is. a) 50 b) 40 c) 70 d) 60

Last Answer : D Let distance = x km Rate = y km/hr x/y - x / (y+6) = 30/60 (x(y+6)-xy) / y(y+6) = ½ (xy +6x - xy) / y(y+6) = ½ 12x = y(y+6) ------------>1 And x/ (y-4) - x/y = 30/60 (Xy - x(y-4 ... = (y+6) / (y-4) 3y - 12 = 2y +12 Y = 24km Put y value in 1 we get 12x = 24 (24+6) 12x = 24 *30 X=60km

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 : 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 : Pipe A can fill a tank in 4 hours, then time taken by it to fill 3/4th part of the tank is ……………

Last Answer : Pipe A can fill a tank in 4 hours, then time taken by it to fill 3/4th part of the tank is ……………

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 : A person walking 5/6 of his usual rate is 40 minutes late. What is his usual time?

Last Answer : Answer: 3 hours 20 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 : One tap can fill a tank thrice as fast as another tap. If together the two taps can fill the tank in 12 minutes, then the slower tap alone will be able to fill the tank in A) 30min B) 33min C) 32min D) 35min

Last Answer : C (1/x)+(1/3x)=(1/12) 3+1/3x = 4/3x = 1/12 3x = 48 x=32mins

Description : Bucket A has twice the capacity as bucket B. It takes 120 turns for bucket A to fill the empty dumper. How many turns it will take for both the buckets A and B, having each turn together to fill the empty dumper. A) 40 B) 50 C) 70 D) 80

Last Answer : D Let capacity of A be x litres Then capacity of B = x/2 litres Capacity of the dumper = 120x litres Required number of turns = 120x/ x =x/2 = 2 (120x)/3x =2430x/3x =80.

Description : Faucet A and B can fill a tank in 15 and 9 hrs respectively. Faucet C can empty it in 45 h. The tank is half full. All the three faucets are in operation simultaneously. After how much time the tank will be full ? A) 1(7/15)hrs B) 2(1/11)hrs C) 3(3/14)hrs D) 3(3/11)hrs

Last Answer : C In 1 hr = 1/15+1/9 – 1/45 =>3+5-1/45 = 7/45 ½ tank filled by 3 Faucets = 45/7*1/2 => 45/14 =>3(3/14)

Description : The detention period in a septic tank is assumed (A) 20 minutes (B) 25 minutes (C) 30 minutes (D) 40 minute

Last Answer : (C) 30 minutes

Description : Faucet 'P' can fill the tank completely in12 hrs while faucet'q' can empty it by 24 hrs. By mistake, Anitha forgot to close the faucet q', As a result, both the faucet remained open. After 8 hrs, faucet realized the ... '. In how much time now onwards, would the tank be full? A) 4 B) 8 C) 12 D) 16 

Last Answer : Answer: B Explanation: Faucet P can fill the tank completely in 12 hours => In 1 hour, Faucet P can fill 1/12of the tank Faucet q can empty the tank completely in 24 hours => In 1 hour, Faucet q can empty ... tank. Time taken to fill the remaining (1−1/3)=2/3of the tank =(2/3)/(1/12) = 8 hours

Description : Minimum horsepower of pump required for filling 50m3 water tank, 20 metres high from ground in 30 minutes by lifting water from a well 5 metres below the ground level is a.5.45 KW b.7.5 KW c.6.81 KW d.Tapered bearing e.66.8 KW

Last Answer : c. 6.81 KW

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 wizard named Nepo says "I am only three times my son's age. My father is 40 years more than twice my age. Together the three of us are a mere 1240 years old." How old is Nepo?

Last Answer : Answer: 360 years old.

Description : A boys rows to a certain place and comes back, but by mistake he covers 2/3rd more distance while coming back. The total time for this journey is 20 hours. The ratio of speed of boat to that of ... starting point from his present position? A) 2hr 13mints B)1hr 30 mins C) 2hr 30mins D)1hr 40 mins

Last Answer : ANSWER : A Explanation: let speed of boat and stream be 2x and x respectively So downstream speed = 2x+x = 3x, and upstream speed = 2x-x = x Let total distance between points is d km So he covered d ... with speed 3x = 48 km/hr(downstream) So time is 80/36 * 60 = 133.33 minutes = 2hr 13mins

Description : In covering a definite distance, the speeds of P & Q are in the ratio of 5:6. P takes 45 mins more than Q to reach the target. The time taken by P to reach the target is. a) 4 hrs 20 mins b) 4 hrs 45 mins c) 2hrs 30 mins d) 4hrs 30 mins

Last Answer : D Ratio of speeds = 5:6 Ratio of time =6:5 Suppose P takes 6x hrs and Q takes 5x hrs to reach the target. Then, 6x – 5x = 45/60 X=3/4 Time taken by P = 6x hrs =(6*3/4)hrs =4.5 hrs i.e., the time taken by P to reach the target is 4hrs 30mins