Time and Work Quants MCQs with Answer - Exercise V


Ques 1 Time and Work

If A and B together can complete a work 18 days, A and C together in 12 days, and B and C together in 9 days, then B alone can do the work in?
  a) 12 days
  b) 24 days
  c) 30 days
  d) 40 days


b is the correct option
(A + B)'s one day work = 1/18.
(A + C)'s one day work = 1/12.
(B + C)'s one day work = 1/9.
Adding all three equations and dividing by 2.
2(A + B + C)'s one day work = (1/18) + (1/12) + (1/9) = 1/8.
B's one day work = (A + B + C)'s one day work - (A + C)'s one day work.
= 1/8 - 1/12 = 1/24.
Therefore, B alone can complete the work in 24 days.




Ques 2 Time and Work

A can complete a task in 6 days, while B can complete the same task in 12 days. How many days will they take to complete the same task if they work together?
  a) 3
  b) 4.5
  c) 4
  d) 5


c is the correct option
A's one day work = 1/6.
B's one day work = 1/12.
(A + B)'s one day work = (1/6) + (1/12) = 1/4.
Time to complete the work together = 1 / (1/4) = 4 days.




Ques 3 Time and Work

A can complete one-sixth of a work in 5 days and B can complete one-fourth of the same work in 15 days. In how many days, will both working together complete the work?
  a) 20 days
  b) 25 days
  c) 10 days
  d) 12 days


a is the correct option
A can do 1/6 of the job in 5 days, so he can finish the whole job in 30 days (6 x 5).
B can do 1/4 of the job in 15 days, so he can finish the whole job in 60 days (4 x 15).
When they work together, they do more work each day.
A does 1/30 of the job in a day.
B does 1/60 of the job in a day.
Together, they do 1/30 + 1/60 = 1/20 of the job in a day.
So, they will finish the whole job in 20 days.




Ques 4 Time and Work

15 persons working 6 hours per day earn ₹900. How much money will 20 persons earn, working 10 hours per day?
  a) ₹1,800
  b) ₹2,000
  c) ₹1,500
  d) ₹2,100


b is the correct option




Ques 5 Time and Work

A pipe is filling a tank of 200 litres capacity at 5 litres/hr. Because of a leak it takes 80 hours more to fill the tank. What is the rate in litres/hr at which the water is leaking?
  a) 6
  b) 3
  c) 3.33
  d) 8


c is the correct option