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Number of Questions: 10
Time: 10 Minutes
Category: Aptitude
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Question 1 of 30
1. Question
A does half as much work as B in threefourth of the time. If together they take 18 days to complete the work, how much time shall B take to do it
Correct
Answer: Option C
Explanation:
Suppose B takes x dáys to do the work.
As per question A will take
2∗3/4∗x=3x/2days
(A+B)s 1 days work= 1/18
1/x + 2/3x = 1/18 or x = 30 daysIncorrect
Answer: Option C
Explanation:
Suppose B takes x dáys to do the work.
As per question A will take
2∗3/4∗x=3x/2days
(A+B)s 1 days work= 1/18
1/x + 2/3x = 1/18 or x = 30 days 
Question 2 of 30
2. Question
A is thrice as good a workman as B and takes 10 days less to do a piece of work than B takes. B alone can do the whole work in
Correct
Answer: Option A
Explanation:
Ratio of times taken by A and B = 1:3
Means B will take 3 times which A will do in 1 timeIf difference of time is 2 days, B takes 3 days
If difference of time is 10 days, B takes (3/2) * 10 =15 daysIncorrect
Answer: Option A
Explanation:
Ratio of times taken by A and B = 1:3
Means B will take 3 times which A will do in 1 timeIf difference of time is 2 days, B takes 3 days
If difference of time is 10 days, B takes (3/2) * 10 =15 days 
Question 3 of 30
3. Question
4 men and 6 women finish a job in 8 days, while 3 men and 7 women finish it in 10 days. In how many days will 10 women working together finish it ?
Correct
Answer: Option B
Explanation:
Let 1 man’s 1 day work = x
and 1 woman’s 1 days work = y.
Then, 4x + 6y = 1/8
and 3x+7y = 1/10
solving, we get y = 1/400 [means work done by a woman in 1 day]10 women 1 day work = 10/400 = 1/40
10 women will finish the work in 40 days
Incorrect
Answer: Option B
Explanation:
Let 1 man’s 1 day work = x
and 1 woman’s 1 days work = y.
Then, 4x + 6y = 1/8
and 3x+7y = 1/10
solving, we get y = 1/400 [means work done by a woman in 1 day]10 women 1 day work = 10/400 = 1/40
10 women will finish the work in 40 days

Question 4 of 30
4. Question
5 men and 2 boys working together can do four times as much work as a man and a boy. Working capacity of man and boy is in the ratio
Correct
Answer: Option C
Explanation:
Let 1 man 1 day work = x
1 boy 1 day work = ythen 5x + 2y = 4(x+y)
=> x = 2y
=> x/y = 2/1
=> x:y = 2:1Incorrect
Answer: Option C
Explanation:
Let 1 man 1 day work = x
1 boy 1 day work = ythen 5x + 2y = 4(x+y)
=> x = 2y
=> x/y = 2/1
=> x:y = 2:1 
Question 5 of 30
5. Question
A and B can together finish a work 30 days. They worked together for 20 days and then B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the work?
Correct
Answer: Option D
Explanation:
(A + B)’s 20 day’s work = (1/30 *20)=2/3
Remaining work =(12/3)=1/3
Now,1/3 work is done by A in 20 days.Therefore, the whole work will be done by A in (20 x 3) = 60 days.
Incorrect
Answer: Option D
Explanation:
(A + B)’s 20 day’s work = (1/30 *20)=2/3
Remaining work =(12/3)=1/3
Now,1/3 work is done by A in 20 days.Therefore, the whole work will be done by A in (20 x 3) = 60 days.

Question 6 of 30
6. Question
A and B together can do a piece of work in 30 days. A having worked for 16 days, B finishes the remaining work alone in 44 days. In how many days shall B finish the whole work alone?
Correct
Answer: Option C
Explanation:
Let A’s 1 day’s work = x and B’s 1 day’s work = y.
Then, x + y = 1/30 and 16x + 44y = 1.
Solving these two equations, we get: x =1/60and y =1/60
B’s 1 day’s work =1/60.
Hence, B alone shall finish the whole work in 60 days.Incorrect
Answer: Option C
Explanation:
Let A’s 1 day’s work = x and B’s 1 day’s work = y.
Then, x + y = 1/30 and 16x + 44y = 1.
Solving these two equations, we get: x =1/60and y =1/60
B’s 1 day’s work =1/60.
Hence, B alone shall finish the whole work in 60 days. 
Question 7 of 30
7. Question
If 5 women or 8 girls can do a work in 84 days. In how many days can 10 women and 5 girls can do the same work?
Correct
Answer : A.
Given that 5 women is equal to 8 girls to complete a work.
So, 10 women = 16 girls.
Therefore 10 women + 5 girls = 16 girls + 5 girls = 21 girls.
8 girls can do a work in 84 days then 21 girls can do a work in (8*84/21) = 32 days.
Therefore 10 women and 5 girls can a work in 32 daysIncorrect
Answer : A.
Given that 5 women is equal to 8 girls to complete a work.
So, 10 women = 16 girls.
Therefore 10 women + 5 girls = 16 girls + 5 girls = 21 girls.
8 girls can do a work in 84 days then 21 girls can do a work in (8*84/21) = 32 days.
Therefore 10 women and 5 girls can a work in 32 days 
Question 8 of 30
8. Question
An employer pays Rs. 30 for each day a worker works, and forfeits Rs. 5 for each day he is idle. At the end of 60 days, a worker gets Rs. 500. For how many days did the worker remain idle?
Correct
ANSWER:C
Explanation:
Suppose the worker remained idle for m days. Then, he worked for (60 – m) days.
30 (60 – m) – 5m = 500
1800 – 25m = 500
25m = 1300
m = 52
So, the worker remained idle for 52 days.Incorrect
ANSWER:C
Explanation:
Suppose the worker remained idle for m days. Then, he worked for (60 – m) days.
30 (60 – m) – 5m = 500
1800 – 25m = 500
25m = 1300
m = 52
So, the worker remained idle for 52 days. 
Question 9 of 30
9. Question
5/8th of a job is completed in 10 days. If a person works at the same pace, how many days will he take to complete the job?
Correct
ANSWER: C
Explanation:
Solution: It is given that 5/8th of the work is completed in 10 days.=> Remaining work = 3/8th of total
Applying unitary method:
Total work will be completed in 10 * 8 / 5 days
=> It takes 16 days to complete total work
=> Hence, remaining work days = 16 – 10 = 6 days
Incorrect
ANSWER: C
Explanation:
Solution: It is given that 5/8th of the work is completed in 10 days.=> Remaining work = 3/8th of total
Applying unitary method:
Total work will be completed in 10 * 8 / 5 days
=> It takes 16 days to complete total work
=> Hence, remaining work days = 16 – 10 = 6 days

Question 10 of 30
10. Question
Pooja is twice as efficient as Aarti and takes 90 days less than Aarti to complete the job. Find the time in which they can finish the job together.
Correct
Correct answer :(c)
Since ‘A’ is ‘m’ times as efficient as ‘B’ & takes ‘D’ days less than ‘B’, then the time required to complete the job together is given by,
T = m x D/(m2 – 1)
T = 2 x 90 / [(2)2 – 1] = 180 / 3 = 60 daysIncorrect
Correct answer :(c)
Since ‘A’ is ‘m’ times as efficient as ‘B’ & takes ‘D’ days less than ‘B’, then the time required to complete the job together is given by,
T = m x D/(m2 – 1)
T = 2 x 90 / [(2)2 – 1] = 180 / 3 = 60 days 
Question 11 of 30
11. Question
Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same Job.How long should it take both A and B, working together but independently, to do the same job?
Correct
A’s 1 hour’s work = 1/8
B’s 1 hour’s work = 1/10
(A + B)’s 1 hour’s work = (1/8) +(1/10)=9/40
Both A and B will finish the work in 40/9 days.
Incorrect
A’s 1 hour’s work = 1/8
B’s 1 hour’s work = 1/10
(A + B)’s 1 hour’s work = (1/8) +(1/10)=9/40
Both A and B will finish the work in 40/9 days.

Question 12 of 30
12. Question
A and B together can complete a piece of work in 4 days. If A alone can complete the same work in 12 days, in how many days can B alone complete that work?
Correct
(A + B)’s 1 day’s work = (1/4). A’s 1 day’s work = (1/12).
B’s 1 day’s work =((1/4)(1/12))=(1/6)
Hence, B alone can complete the work in 6 days.
Incorrect
(A + B)’s 1 day’s work = (1/4). A’s 1 day’s work = (1/12).
B’s 1 day’s work =((1/4)(1/12))=(1/6)
Hence, B alone can complete the work in 6 days.

Question 13 of 30
13. Question
A can do a piece of work in 7 days of 9 hours each and B can do it in 6 days of 7 bours each. How long will they take to do it, working together 8 hours a day?
Correct
A can complete the work in (7 x 9) = 63 hours.
B can complete the work in (6 x 7) = 42 hours.
A’s 1 hour’s work = (1/63) and B’s 1 hour’s work =(1/42)
(A + B)’s 1 hour’s work =(1/63)+(1/42)=(5/126)
Both will finish the work in (126/5) hrs.
Number of days. of (42/5) hrs each =(126 x 5)/(5 x 42)=3 days
Incorrect
A can complete the work in (7 x 9) = 63 hours.
B can complete the work in (6 x 7) = 42 hours.
A’s 1 hour’s work = (1/63) and B’s 1 hour’s work =(1/42)
(A + B)’s 1 hour’s work =(1/63)+(1/42)=(5/126)
Both will finish the work in (126/5) hrs.
Number of days. of (42/5) hrs each =(126 x 5)/(5 x 42)=3 days

Question 14 of 30
14. Question
A and B can do a piece of work in 18 days; Band C can do it in 24 days A and C can do it in 36 days. In how many days will A, Band C finish it together and separately?
Correct
A + B)’s 1 day’s work = (1/18) (B + C)’s 1 day’s work = (1/24)
and (A + C)’s 1 day’s work = (1/36)
Adding, we get: 2 (A + B + C)’s 1 day’s work =(1/18 + 1/24 + 1/36)
=9/72 =1/8
(A +B + C)’s 1 day’s work =1/16
Thus, A, Band C together can finish the work in 16 days.
Now, A’s 1 day’s work = [(A + B + C)’s 1 day’s work] – [(B + C)’s 1 day work:
=(1/16 – 1/24)= 1/48
A alone can finish the work in 48 days.
Similarly, B’s 1 day’s work =(1/16 – 1/36)=5/144
B alone can finish the work in 144/5=28 4/5 days
And C’s 1 day work =(1/161/18)=1/144
Hence C alone can finish the work in 144 days.
Incorrect
A + B)’s 1 day’s work = (1/18) (B + C)’s 1 day’s work = (1/24)
and (A + C)’s 1 day’s work = (1/36)
Adding, we get: 2 (A + B + C)’s 1 day’s work =(1/18 + 1/24 + 1/36)
=9/72 =1/8
(A +B + C)’s 1 day’s work =1/16
Thus, A, Band C together can finish the work in 16 days.
Now, A’s 1 day’s work = [(A + B + C)’s 1 day’s work] – [(B + C)’s 1 day work:
=(1/16 – 1/24)= 1/48
A alone can finish the work in 48 days.
Similarly, B’s 1 day’s work =(1/16 – 1/36)=5/144
B alone can finish the work in 144/5=28 4/5 days
And C’s 1 day work =(1/161/18)=1/144
Hence C alone can finish the work in 144 days.

Question 15 of 30
15. Question
A is twice as good a workman as B and together they finish a piece in 18 days. In how many days will A alone finish the work?
Correct
(A’s 1 day’s work):)(B’s 1 days work) = 2 : 1.
(A + B)’s 1 day’s work = 1/18
Divide 1/18 in the ratio 2 : 1.
:. A’s 1 day’s work =(1/18*2/3)=1/27
Hence, A alone can finish the work in 27 days.
Incorrect
(A’s 1 day’s work):)(B’s 1 days work) = 2 : 1.
(A + B)’s 1 day’s work = 1/18
Divide 1/18 in the ratio 2 : 1.
:. A’s 1 day’s work =(1/18*2/3)=1/27
Hence, A alone can finish the work in 27 days.

Question 16 of 30
16. Question
A can do a certain job in 12 days. B is 60% more efficient than A. How many days does B alone take to do the same job?
Correct
Ratio of times taken by A and B = 160 : 100 = 8 : 5.
Suppose B alone takes x days to do the job.
Then, 8 : 5 :: 12 : x = 8x = 5 x 12 =x = 7 1/2 days.
Incorrect
Ratio of times taken by A and B = 160 : 100 = 8 : 5.
Suppose B alone takes x days to do the job.
Then, 8 : 5 :: 12 : x = 8x = 5 x 12 =x = 7 1/2 days.

Question 17 of 30
17. Question
A can do a piece of work in 80 days. He works at it for 10 days B alone finishes the remaining work in 42 days. In how much time will A and B working together, finish the work?
Correct
Work done by A in 10 days =(1/80*10)=1/8
Remaining work = (1 1/8) =7/ 8
Now,7/ 8 work is done by B in 42 days.
Whole work will be done by B in (42 x 8/7) = 48 days.
A’s 1 day’s work = 1/80 and B’s 1 day’s work = 1/48
(A+B)’s 1 day’s work = (1/80+1/48)=8/240=1/30
Hence, both will finish the work in 30 days
Incorrect
Work done by A in 10 days =(1/80*10)=1/8
Remaining work = (1 1/8) =7/ 8
Now,7/ 8 work is done by B in 42 days.
Whole work will be done by B in (42 x 8/7) = 48 days.
A’s 1 day’s work = 1/80 and B’s 1 day’s work = 1/48
(A+B)’s 1 day’s work = (1/80+1/48)=8/240=1/30
Hence, both will finish the work in 30 days

Question 18 of 30
18. Question
A and B undertake to do a piece of work for Rs. 600. A alone can do it in 6 days while B alone can do it in 8 days. With the help of C, they finish it in 3 days. !find the share of each.
Correct
C’s 1 day’s work = 1/3(1/6+1/8)=24
A : B : C = Ratio of their 1 day’s work = 1/6:1/8:1/24= 4 : 3 : 1.
A’s share = Rs. (600 *4/8) = Rs.300, B’s share = Rs. (600 *3/8) = Rs. 225.
C’s share = Rs. [600 – (300 + 225») = Rs. 75.
Incorrect
C’s 1 day’s work = 1/3(1/6+1/8)=24
A : B : C = Ratio of their 1 day’s work = 1/6:1/8:1/24= 4 : 3 : 1.
A’s share = Rs. (600 *4/8) = Rs.300, B’s share = Rs. (600 *3/8) = Rs. 225.
C’s share = Rs. [600 – (300 + 225») = Rs. 75.

Question 19 of 30
19. Question
A and B working separately can do a piece of work in 9 and 12 days respectively, If they work for a day alternately, A beginning, in how many days, the work will be completed?
Correct
(A + B)’s 2 days’ work =(1/9+1/12)=7/36
Work done in 5 pairs of days =(5*7/36)=35/36
Remaining work =(135/36)=1/36
On 11th day, it is A’s turn. 1/9 work is done by him in 1 day.
1/36 work is done by him in(9*1/36)=1/4 day
Total time taken = (10 + 1/4) days = 10 1/4days.
Incorrect
(A + B)’s 2 days’ work =(1/9+1/12)=7/36
Work done in 5 pairs of days =(5*7/36)=35/36
Remaining work =(135/36)=1/36
On 11th day, it is A’s turn. 1/9 work is done by him in 1 day.
1/36 work is done by him in(9*1/36)=1/4 day
Total time taken = (10 + 1/4) days = 10 1/4days.

Question 20 of 30
20. Question
45 men can complete a work in 16 days. Six days after they started working, 30 more men joined them. How many days will they now take to complete the remaining work?
Correct
(45 x 16) men can complete the work in 1 day.
1 man’s 1 day’s work = 1/720
45 men’s 6 days’ work =(1/16*6)=3/8
Remaining work =(13/8)=5/8
75 men’s 1 day’s work = 75/720=5/48
Now,5 work is done by them in 1 day.
48
5work is done by them in (48 x 5)=6 days.
8 5 8
Incorrect
(45 x 16) men can complete the work in 1 day.
1 man’s 1 day’s work = 1/720
45 men’s 6 days’ work =(1/16*6)=3/8
Remaining work =(13/8)=5/8
75 men’s 1 day’s work = 75/720=5/48
Now,5 work is done by them in 1 day.
48
5work is done by them in (48 x 5)=6 days.
8 5 8

Question 21 of 30
21. Question
2 men and 3 boys can do a piece of work in 10 days while 3 men and 2 boys can do the same work in 8 days.In how many days can 2 men and 1 boy do the work?
Correct
: Let 1 man’s 1 day’s work = x and 1 boy’s 1 day’s work = y.
Then, 2x+3y = 1 and 3x+2y = 1
 8
Solving,we get: x = 7 and y = 1
200 100
(2 men + 1 boy)’s 1 day’s work = (2 x 7 + 1 x 1 ) = 16 = 2
200 100 200 25
So, 2 men and 1 boy together can finish the work in 25 =12 1 days
2 2
Incorrect
: Let 1 man’s 1 day’s work = x and 1 boy’s 1 day’s work = y.
Then, 2x+3y = 1 and 3x+2y = 1
 8
Solving,we get: x = 7 and y = 1
200 100
(2 men + 1 boy)’s 1 day’s work = (2 x 7 + 1 x 1 ) = 16 = 2
200 100 200 25
So, 2 men and 1 boy together can finish the work in 25 =12 1 days
2 2

Question 22 of 30
22. Question
A can do a piece of work in 30 days. He works at it for 5 days and then B finishes it in 20 days. In what time can A and B together it?
Correct
5/30 + 20/x = 1
x = 24
1/30 + 1/24 = 3/40
40/3 = 13 1/3 days
Incorrect
5/30 + 20/x = 1
x = 24
1/30 + 1/24 = 3/40
40/3 = 13 1/3 days

Question 23 of 30
23. Question
A take twice as much time as B or thrice as much time to finish a piece of work. Working together, they can finish the work in 2 days. B can do the work alone in?
Correct
Suppose A, B and C take x, x/2 and x/3 respectively to finish the work.
Then, (1/x + 2/x + 3/x) = 1/26/x = 1/2 => x = 12So, B takes 6 hours to finish the work.Incorrect
Suppose A, B and C take x, x/2 and x/3 respectively to finish the work.
Then, (1/x + 2/x + 3/x) = 1/26/x = 1/2 => x = 12So, B takes 6 hours to finish the work. 
Question 24 of 30
24. Question
10 men and 15 women together can complete a work in 6 days. It takes 100 days for one man alone to complete the same work. How many days will be required for one woman alone to complete the same work?
Correct
1 man’s 1 day work = 1/100
(10 men + 15 women)’s 1 day work = 1/615 women’s 1 day work = (1/6 – 10/100) = 1/151 woman’s 1 day work = 1/2251 woman alone can complete the work in 225 days.Incorrect
1 man’s 1 day work = 1/100
(10 men + 15 women)’s 1 day work = 1/615 women’s 1 day work = (1/6 – 10/100) = 1/151 woman’s 1 day work = 1/2251 woman alone can complete the work in 225 days. 
Question 25 of 30
25. Question
3 men, 4 women and 6 children can complete a work in 7 days. A woman does double the work a man does and a child does half the work a man does. How many women alone can complete this work in 7 days?
Correct
Let 1 woman’s 1 day work = x.
Then, 1 man’s 1 day work = x/2 and 1 child’s 1 day work x/4.So, (3x/2 + 4x + + 6x/4) = 1/728x/4 = 1/7 => x = 1/491 woman alone can complete the work in 49 days.So, to complete the work in 7 days, number of women required = 49/7 = 7.Incorrect
Let 1 woman’s 1 day work = x.
Then, 1 man’s 1 day work = x/2 and 1 child’s 1 day work x/4.So, (3x/2 + 4x + + 6x/4) = 1/728x/4 = 1/7 => x = 1/491 woman alone can complete the work in 49 days.So, to complete the work in 7 days, number of women required = 49/7 = 7. 
Question 26 of 30
26. Question
A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days A do the work if he is assisted by B and C on every third day?
Correct
A’s 2 day’s work = (1/20 * 2) = 1/10
(A + B + C)’s 1 day work = (1/20 + 1/30 + 1/60) = 1/10Work done in 3 days = (1/10 + 1/10) = 1/5Now, 1/5 work is done in 3 days.Whole work will be done in (3 * 5) = 15 days.Incorrect
A’s 2 day’s work = (1/20 * 2) = 1/10
(A + B + C)’s 1 day work = (1/20 + 1/30 + 1/60) = 1/10Work done in 3 days = (1/10 + 1/10) = 1/5Now, 1/5 work is done in 3 days.Whole work will be done in (3 * 5) = 15 days. 
Question 27 of 30
27. Question
20 women can do a work in 9 days. After they have worked for 6 days. 6 more men join them. How many days will they take to complete the remaining work?
Correct
(20 * 16) women can complete the work in 1 day.
1 woman’s 1 day work = 1/320(16 * 15) men can complete the work in 1 day1 man’s 1 day work = 1/240So, required ratio = 1/240 : 1/320 = 4:3.Incorrect
(20 * 16) women can complete the work in 1 day.
1 woman’s 1 day work = 1/320(16 * 15) men can complete the work in 1 day1 man’s 1 day work = 1/240So, required ratio = 1/240 : 1/320 = 4:3. 
Question 28 of 30
28. Question
Ronald and Elan are working on an assignment. Ronald takes 6 hrs to type 32 pages on a computer, while Elan takes 5 hrs to type 40 pages. How much time will they take, working together on two different computers to type an assignment of 110 pages?
Correct
Number of pages typed by Ronald in 1 hour = 32/6 = 16/3
Number of pages typed by Elan in 1 hour = 40/5 = 8Number of pages typed by both in 1 hour = (16/3 + 8) = 40/3Time taken by both to type 110 pages = (110 * 3/40) = 8 1/4 = 8 hrs 15 minIncorrect
Number of pages typed by Ronald in 1 hour = 32/6 = 16/3
Number of pages typed by Elan in 1 hour = 40/5 = 8Number of pages typed by both in 1 hour = (16/3 + 8) = 40/3Time taken by both to type 110 pages = (110 * 3/40) = 8 1/4 = 8 hrs 15 min 
Question 29 of 30
29. Question
A can do a piece of work in 4 hours; B and C together can do it in 3 hours, which A and C together can do it in 2 hours. How long will B alone take to do it?
Correct
A’s 1 hour work = 1/4;
(B + C)’s 1 hour work = 1/3;(A + C)’s 1 hour work = 1/2(A + B + C)’s 1 hour work = (1/4 + 1/3) = 7/12B’s 1 hour work = (7/12 + 1/2) = 1/12B alone will take 12 hours to do the work.Incorrect
A’s 1 hour work = 1/4;
(B + C)’s 1 hour work = 1/3;(A + C)’s 1 hour work = 1/2(A + B + C)’s 1 hour work = (1/4 + 1/3) = 7/12B’s 1 hour work = (7/12 + 1/2) = 1/12B alone will take 12 hours to do the work. 
Question 30 of 30
30. Question
A and B can do a work in 12 days, B and C in 15 days, C and A in 20 days. If A, B and C work together, they will complete the work in?
Correct
(A + B)’s 1 day work = 1/12;
(B + C)’s 1 day work = 1/15;(A + C)’s 1 day work = 1/20Adding, we get: 2(A + B + C)’s 1 day work = (1/12 + 1/15 + 1/20) = 1/5(A + B + C)’s 1 day work = 1/10So, A, B and C together can complete the work in 10 days.Incorrect
(A + B)’s 1 day work = 1/12;
(B + C)’s 1 day work = 1/15;(A + C)’s 1 day work = 1/20Adding, we get: 2(A + B + C)’s 1 day work = (1/12 + 1/15 + 1/20) = 1/5(A + B + C)’s 1 day work = 1/10So, A, B and C together can complete the work in 10 days.