Quantitative Aptitude Questions and Answers - Time and Work
11. Arul can do a certain work in 9 days while Ravi can do the same work in 7 days. Both of them complete
the work together and get Rs.288. what is the share of Arul?
Explanation: Arul's 1 day work = 1/9
Ravi's 1 day work = 1/7
Arul's salary : Ravi's salary = Arul's 1 day work : Ravi's 1 day work
= 1/9 : 1/7
= 7 :9
Arul’s share = Rs.(7/16 *288) => Rs.126
12. 6 male , 8 female and 12 children can complete a work in 14 days .a female does twice the work of a
male does and a child does half the work a male does . how many female alone can complete this work in 14
Explanation: Let 1 female 's 1 day work= x
Then 1 male's 1 day work =x/2
And 1 child's 1 day work =x/4
So 6x/2 + 8x +12x/4 =1/14
3x+8x+3x = 1/14
14x = 1/14
1 female alone can complete the work in 196 days
So, to complete the work in 14 days number of female required = 14.
13. 8 male can finish a work in 6 days.12 female can complete the same work in 9 days. 6 male and 4 female
started working and after 4 days 3 more female joined them. How many days will they now take to complete
the remaining work?
Explanation: 1 male's 1 day work = 1/48
1 female's 1 day work = 1/108
Work done in 4 days = 4 (6/48 +4/108) => 35/54
Remaining work = (1 – 35/54) = 19/54
(6 male + 7 female)'s 1 day work = 6/48 + 7/108 => 41/216
Now 41/216 work is done by them in 1 day
Therefore time taken = 216/41 * 19/54 = 76/41 days
14. A sum of amount of money is adequate to pay peter’s salary for 42 days and Harish’s salary for 56 days.
The same money is adequate to pay the salary of both for.
Explanation: Let the total money be Rs.x
Peter's 1 day salary = Rs. x/42
Harish 1 day salary = Rs. x/56
(peter+harish)'s 1 day salary = Rs(x/42+x/56) => x/24
Money is adequate to pay the salary of both for 24 days
15. 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?
Explanation: 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
16. Rakchita can do a piece of work in 28 days, while Shreya can do the same work in 42 days.They started
the work together but 6 days before the completion of the work, Rakchita left the work. The total number of
days to complete the work is
Explanation: 6 days before the completion of the work Rakchita left the work means in last 6 days only Shreya has worked alone
So, in last 6 days worked done by Shreya = 6*1/42=6/42=1/7
So, the rest = 1-1/7 =6/7
So 6/7work was done by Rakchita
and Shreya worked together=6/7*70/10 => 420/70 => 6 days
17. Pump A can fill the empty bunker in 6 hours, but due to a leak in the bottom it is filled in 7.5 hours, if the
bunker is full and then Pump A is closed then in how many hours the leak can empty it?
Explanation: Efficiency of A = 16.666%
Effective of leak = 13.333%when there is leakage
So, efficiency of leakage =( Efficiency of A- Effective of leak)
It means due to leakage a full bunker will be empty in 30 hours
18. 48 boys complete a work in 36 days. After they have worked for 24 days, 24 more boys join them. How
many days will they take to complete the remaining work?
Explanation: 1 boy's 1 day's work = 1/(36*48) => 1/1728
48 boy's 24 day's work=48*24/1728=2/3
Remaining work = 1-2/3=1/3
72 boy's 1 day's work =72/1728=1/24
1/24 work is done by them in 1 day.
So, 1/3 work is done by them in 24/3= 8 days
19. P, Q and R together earn Rs.420 per day, while P and R together earn Rs.296 and Q and R together earn
Rs.164. The daily earning of R is :
Explanation: (P+Q+R)'s earning = Rs. 420
(P+R)'s earning=Rs 296
(Q+R)'s earning=Rs 164
Q's daily earning = Rs. (420 - 296) = Rs.124
P's daily earning = Rs. (420 - 164) = Rs.236
Now (P+Q)'s earning=Rs 360
R's daily earning = Rs. [420 - 360] = Rs.60
20. A and B together can complete a work in 24 days. A alone can complete it in 40 days. If B does the work
only for half a day daily, then in how many days A and B together will complete the work?
Explanation: B's 1 day's work = (1/24 -1/40) => (5-3)/120 => 2/120 => 1/60c
Now, (A + B)'s 1 day's work = (1/40 +1/60)
=(3+2)/120 => 5/120
So, A and B together will complete the work in 120/5 = 24 days.