time and work problems shortcuts - Wikitechy https://www.wikitechy.com/interview-questions/tag/time-and-work-problems-shortcuts/ Interview Questions Mon, 06 Sep 2021 09:19:34 +0000 en-US hourly 1 https://wordpress.org/?v=6.9 https://www.wikitechy.com/interview-questions/wp-content/uploads/2025/10/cropped-wikitechy-icon-32x32.png time and work problems shortcuts - Wikitechy https://www.wikitechy.com/interview-questions/tag/time-and-work-problems-shortcuts/ 32 32 A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every third day ? https://www.wikitechy.com/interview-questions/time-and-work/a-b-and-c-can-do-a-piece-of-work-in-20-30-and-60-days-respectively-in-how-many-days-can-a-do-the-work-if-he-is-assisted-by-b-and-c-on-every-third-day/ https://www.wikitechy.com/interview-questions/time-and-work/a-b-and-c-can-do-a-piece-of-work-in-20-30-and-60-days-respectively-in-how-many-days-can-a-do-the-work-if-he-is-assisted-by-b-and-c-on-every-third-day/#respond Wed, 18 Aug 2021 03:08:04 +0000 https://www.wikitechy.com/interview-questions/?p=2090

A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every third day ?

A. 18

B. 12

C. 15

D. 14

Answer : C. 15

Explanation:

A’s 2 day’s work = 1/20 x 2
= 1/10
(A + B + C) 1 day’s Work = (1/20 + 1/30 + 1/60)
= 6/60
= 1/10
Now,
Work done in 3 days = (1/10) + (1/10)
= 1/5
Now 1/5 work is done in 3 days.
Now whole work will be done in 3 * 5 = 15 days.

]]> https://www.wikitechy.com/interview-questions/time-and-work/a-b-and-c-can-do-a-piece-of-work-in-20-30-and-60-days-respectively-in-how-many-days-can-a-do-the-work-if-he-is-assisted-by-b-and-c-on-every-third-day/feed/ 0 A alone can do 1/4th of the work in 2 days. B alone can do 2/3rd of the work in 4 days. If all the three work together, they can complete it in 3 days so what part of the work will be completed by C in 2 days ? https://www.wikitechy.com/interview-questions/time-and-work/a-alone-can-do-1-4th-of-the-work-in-2-days-b-alone-can-do-2-3rd-of-the-work-in-4-days-if-all-the-three-work-together-they-can-complete-it-in-3-days-so-what-part-of-the-work-will-be-completed-by-c-i/ https://www.wikitechy.com/interview-questions/time-and-work/a-alone-can-do-1-4th-of-the-work-in-2-days-b-alone-can-do-2-3rd-of-the-work-in-4-days-if-all-the-three-work-together-they-can-complete-it-in-3-days-so-what-part-of-the-work-will-be-completed-by-c-i/#respond Wed, 18 Aug 2021 03:03:11 +0000 https://www.wikitechy.com/interview-questions/?p=2087

A alone can do 1/4th of the work in 2 days. B alone can do 2/3rd of the work in 4 days. If all the three work together, they can complete it in 3 days so what part of the work will be completed by C in 2 days ?

A. 1/12

B. 1/8

C. 1/6

D. 1/20

Answer : A. 1/12

Explanation:

A can do the total work in 8 days, and B can do it in 6 days.

Let the total work be 24 units.

Now,
A = 24/8 = 3
B = 24/6 = 4
A + B + C = 24/3 = 8

So Capacity of C = 1 unit.
In two days C will do 2 units which is 2/24th part of the total work. So 1/12th part.

]]> https://www.wikitechy.com/interview-questions/time-and-work/a-alone-can-do-1-4th-of-the-work-in-2-days-b-alone-can-do-2-3rd-of-the-work-in-4-days-if-all-the-three-work-together-they-can-complete-it-in-3-days-so-what-part-of-the-work-will-be-completed-by-c-i/feed/ 0 Jake can dig a well in 16 days. Paul can dig the same well in 24 days. Jake, Paul and Hari together dig the well in 8 days. Hari alone can dig the well in ? https://www.wikitechy.com/interview-questions/time-and-work/jake-can-dig-a-well-in-16-days-paul-can-dig-the-same-well-in-24-days-jake-paul-and-hari-together-dig-the-well-in-8-days-hari-alone-can-dig-the-well-in/ https://www.wikitechy.com/interview-questions/time-and-work/jake-can-dig-a-well-in-16-days-paul-can-dig-the-same-well-in-24-days-jake-paul-and-hari-together-dig-the-well-in-8-days-hari-alone-can-dig-the-well-in/#respond Wed, 18 Aug 2021 03:01:27 +0000 https://www.wikitechy.com/interview-questions/?p=2086

Jake can dig a well in 16 days. Paul can dig the same well in 24 days. Jake, Paul and Hari together dig the well in 8 days. Hari alone can dig the well in ?

A. 48

B. 96

C. 24

D. 32

Answer : A. 48

Explanation:

As Jake , Paul and Hari can dig the well in 8 days,
Jack one day work = 1/16
Paul one day work = 1/24
Hari one day work = 1/x

Given,
(Jake, Paul and hari) 1 day work = 1/8

So, 1/16 + 1/24 + 1/x = 1/8
5/48 + 1/x = 1/8
1/x = 1/8 – 5/48
1/x = (6 – 5) / 48
= 1/48
1/x = 1/48

Therefore, Paul can finished work in 48 days.

]]> https://www.wikitechy.com/interview-questions/time-and-work/jake-can-dig-a-well-in-16-days-paul-can-dig-the-same-well-in-24-days-jake-paul-and-hari-together-dig-the-well-in-8-days-hari-alone-can-dig-the-well-in/feed/ 0 A certain number of answer sheets can be checked in 12 days working 5 hours each day by 9 examiners. For how many hours a day should 4 examiners work to check twice the number of answer sheets in 30 days ? https://www.wikitechy.com/interview-questions/chain-rule/a-certain-number-of-answer-sheets-can-be-checked-in-12-days-working-5-hours-each-day-by-9-examiners-for-how-many-hours-a-day-should-4-examiners-work-to-check-twice-the-number-of-answer-sheets-in-30-d/ https://www.wikitechy.com/interview-questions/chain-rule/a-certain-number-of-answer-sheets-can-be-checked-in-12-days-working-5-hours-each-day-by-9-examiners-for-how-many-hours-a-day-should-4-examiners-work-to-check-twice-the-number-of-answer-sheets-in-30-d/#respond Tue, 17 Aug 2021 22:01:44 +0000 https://www.wikitechy.com/interview-questions/?p=1984

A certain number of answer sheets can be checked in 12 days working 5 hours each day by 9 examiners. For how many hours a day should 4 examiners work to check twice the number of answer sheets in 30 days ?

A. 4 hours

B. 8 hours

C. 7 hours

D. 9 hours

Answer : D. 9 hours

Explanation:

Let required number of hours be x
More examiners, less hours(indirect proportion)
More days, less hours(indirect proportion)
More answer books, more hours(direct proportion)
Hence we can write as

A certain number of answer sheets
    • 9 * 12 * 2 * 5 = 4 * 30 * 1 * x
    • x = 9 * 12 * 2 * 5 / 4 * 30 * 1
    • = 9 * 3 * 2 * 5 / 30
    = 9
]]> https://www.wikitechy.com/interview-questions/chain-rule/a-certain-number-of-answer-sheets-can-be-checked-in-12-days-working-5-hours-each-day-by-9-examiners-for-how-many-hours-a-day-should-4-examiners-work-to-check-twice-the-number-of-answer-sheets-in-30-d/feed/ 0 Dustin is driving his car at speed of 50 kilometres per hour. He going to Texas which is located 345 kilometres from his starting point. How long will it take him to reach Texas https://www.wikitechy.com/interview-questions/time-and-distance/dustin-is-driving-his-car-at-speed-of-50-kilometres-per-hour-he-going-to-texas-which-is-located-345-kilometres-from-his-starting-point-how-long-will-it-take-him-to-reach-texas/ https://www.wikitechy.com/interview-questions/time-and-distance/dustin-is-driving-his-car-at-speed-of-50-kilometres-per-hour-he-going-to-texas-which-is-located-345-kilometres-from-his-starting-point-how-long-will-it-take-him-to-reach-texas/#respond Tue, 17 Aug 2021 21:14:29 +0000 https://www.wikitechy.com/interview-questions/?p=1963

Dustin is driving his car at speed of 50 kilometres per hour. He going to Texas which is located 345 kilometres from his starting point. How long will it take him to reach Texas ?

A. 70

B. 71

C. 72

D. 69

Answer : D. 69

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