8
Q:

Adam and Smith are working on a project. Adam takes 6 hrs to type 36 pages on a computer, while Smith takes 5 hrs to type 40 pages. How much time will they take, working together on two different computers to type a project of 120 pages?

A) 8 hrs 45 min B) 8 hrs 42 min
C) 8 hrs D) 8 hrs 34 min

Answer:   D) 8 hrs 34 min

Explanation:

Number of pages typed by Adam in 1 hour =  = 6
Number of pages typed by Smith in 1 hour =  = 8
Number of pages typed by both in 1 hour = (6 + 8) = 14
Time taken by both to type 110 pages = (120 * 1/14) = 8  = 8 hrs 34 min.

Q:

P and Q can do a work in 4 hours and 12 hours respectively. P starts the work at 9am and they work alternately for one hour each. When will the work be completed ?

A) 3 am B) 12 pm
C) 1 pm D) 3 pm
 
Answer & Explanation Answer: D) 3 pm

Explanation:

Work done by P and Q in the first two hours, working alternately
= First hour P + Second hour Q
  work is completed in 2 hours
Then, the total time required to complete the work by P and Q working alternately=23=6hours
Thus, work will be completed at 3pm.

Report Error

View Answer Workspace Report Error Discuss

4 125
Q:

K is 4 times as fast as L and working together, they can complete a work in 24 days. In how many days can L alone complete the work ?

A) 30 days B) 40 days
C) 120 days D) 80 days
 
Answer & Explanation Answer: A) 30 days

Explanation:

Given K=4L
 K+L = 4L+L = 5L
These 5L people can complete the work in 24 days, which means L alone can do the work in

245=120 days.

Hence, K alone can do the work in  = 30 days.

Report Error

View Answer Workspace Report Error Discuss

3 71
Q:

A, B and C can do a piece of work in 24 days, 30 days and 40 days respectively. They began the work together but C left 4 days before the completion of the work. In how many days was the work completed?

A) 11 days B) 12 days
C) 13 days D) 14 days
 
Answer & Explanation Answer: A) 11 days

Explanation:

One day's work of A, B and C = (1/24 + 1/30 + 1/40) = 1/10

C leaves 4 days before completion of the work, which means only A and B work during the last 4 days.

Work done by A and B together in the last 4 days = 4 (1/24 + 1/30) = 3/10

Remaining Work = 7/10, which was done by A,B and C in the initial number of days. 

Number of days required for this initial work = 7 days.

Thus, the total numbers of days required = 4 + 7 = 11 days.

Report Error

View Answer Workspace Report Error Discuss

20 5916
Q:

A and B can do a work in 4 hours and 12 hours respectively. A starts the work at 6 AM and they work alternately for one hour each. When will the work be completed?

A) 4 days B) 5 days
C) 6 days D) 7 days
 
Answer & Explanation Answer: C) 6 days

Explanation:

Work donee by A and B in the first two hours, working alternatively = First hour A + Second hour B = (1/4) + (1/12) = 1/3.

Thus, the total time required to complete the work  = 2 (3) = 6 days 

Report Error

View Answer Workspace Report Error Discuss

7 1389
Q:

Two pipes A and B can fill a tank in 24 hours and  hours respectively. Harihar opened the pipes A and B to fill an empty tank and some times later he closed the taps A and B , when the tank was supposed to be full. After that it was found that the tank was emptied in 2.5 hours because an outlet pipe "C" connected to the tank was open from the beginning. If Harihar closed the pipe C instead of closing pipes A and B the remaining tank would have been filled in :

A) 2 hours B) 8 hours
C) 6 hours D) 4 hours
 
Answer & Explanation Answer: B) 8 hours

Explanation:

Efficiency of Inlet pipe A = 4.16%                              

Efficiency of Inlet pipe B = 5.83%                              

 Efficiency of A and B together = 100 %  

Now, if the efficiency of outlet pipe be x% then in 10 hours the capacity of tank which will be filled = 10 *  (10 - x)

Now, since this amount of water is being emptied by C at x% per hour, then            

           x = 8%

Therefore, in 10 hours 20% tank is filled only. Hence, the remaining 80% of the  capacity will be filled by pipes A and B  in 80/10 = 8 hours 

Report Error

View Answer Workspace Report Error Discuss

11 783