Daily Numerical Ability Quiz - 20th August 2018

Q1. A water tank normally takes 7 hours to be filled by a tap but because of the leak, it takes another 2 hours. In how many hours will the leak empty a full water tank? 

(a) 20.5 hours 

(b) 24.4 hours 

(c) 30 hours 

(d) 31.5 hours 

(e) None of these 

Q2. A cistern can be filled separately by two pipes P and Q in 45 minutes and 35 minutes respectively. A tap R at the bottom can empty the full cistern in 30 minutes. If the tap R is opened 7 minutes after the two pipes P and Q are opened then after what time from the opening of tap R the cistern becomes full? 

(a) 40th minute 

(b) 61st minute 

(c) 37th minute 

(d) None of these 

(e) Can’t determine 

Q3. Tap A fills a tank in 20 minutes while C empties it at 1/3rd the rate at which A fills it. At 12 : 00 noon, A and C are simultaneously started and when the tank is 50% full, tap A is turned off. At what time will the tank be empty? 

(a) 12 : 35 pm 

(b) 12 : 45 pm 

(c) 12 : 30 pm 

(d) 12 : 55 pm 

(e) None of these 

Q4. Two pipes X and Y can fill a tank in 6  hours and 9 hours respectively. If they are turned on alternately for one hour each starting with X, then what is the time taken to fill the tank?

(a) 6.25 hours 

(b) 5.66 hours 

(c) 7 hours

(d) 8 hours 

(e) None of these 

Q5. Four plumbers had to repair 364 taps. At the end of 3 days working 7 hours per day they had repaired 168 taps. In order to speed up the work, 3 more plumbers were added who also worked 7 hours daily. If the efficiency of each of the plumbers is same, how many additional days would it take to complete the task? 

(a) 2 days 

(b) 3 days 

(c) 4 days 

(d) 3/2day

(e) None of these 

Q6. Pipe A and B can fill a cistern in 10 hours and 15 hours respectively. When a third pipe C which works as an outlet pipe is also open then the cistern can be filled in 18 hours. The outlet pipe can empty a full cistern in:

(a) 12 hours

(b) 8 hours

(c) 9 hours

(d) 14 hours

(e) None of these 

Q7. Two pipes A and B can fill up a half full tank in 1.2 hours. The tank was initially empty. Pipe B was kept open for half the time required by pipe A to fill the tank by itself. Then, pipe A was kept open for as much time as was required by pipe B to fill up 1/3 of the tank by itself. It was then found that the tank was 5/6 full. The least time in which any of the pipes can fill the tank fully is 

(a) 4.8 hours 

(b) 4 hours 

(c) 3.6 hours 

(d) 6 hours 

(e) None of these 

Q8. A tank of capacity 25 litres has an inlet and an outlet tap. If both are opened simultaneously, the tank is filled in 5 minutes. But if the outlet flow rate is doubled and both taps opened the tank never gets filled up. Which of the following can be outlet flow rate in litres/min?

(a) 2

(b) 6

(c) 4

(d) 3

(e) None of these 

Q9. Tap A can fill a tank in 20 hours, B in 25 hours but tap C can empty a full tank in 30 hours. Starting with A, followed by B and C each tap opens alternatively for one hour period till the tank gets filled up completely. In how many hour the tank will be filled up completely? 

Q10. Two pipes A and B can fill a cistern in 15 hours and 10 hours respectively. A tap C can empty the full cistern in 30 hours. All the three taps were open for 2 hours, when it was remembered that the emptying tap had been left open. It was then closed. How many hours more would it take for the cistern to be filled? (relative to the case where the emptying tap was closed before opening the filling pipes A and B)

(a) 30 min.

(b) 1.2 hours

(c) 24 min. 

(d) 35 min. 

(e) None of these