Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 3)
3.
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?
Answer: Option
Explanation:
| A's 2 day's work = |  |
1 | x 2 |  |
= | 1 | . |
| 20 | 10 |
| (A + B + C)'s 1 day's work = | |
1 | + | 1 | + | 1 | |
= | 6 | = | 1 | . |
| 20 | 30 | 60 | 60 | 10 |
| Work done in 3 days = | |
1 | + | 1 | |
= | 1 | . |
| 10 | 10 | 5 |
| Now, | 1 | work is done in 3 days. |
| 5 |
Whole work will be done in (3 x 5) = 15 days.
Discussion:
357 comments Page 7 of 36.
Siddu said:
1 decade ago
Please explain how we will get 6/60 please?
Kamalakannan said:
1 decade ago
Could you tell me? why you take A has done by 2 days work?
Eswarijana said:
1 decade ago
I can't understand the last step.
Renjini said:
1 decade ago
How could get 1/5? I can't understand.
Tania said:
1 decade ago
@kamalakannan
Because A alone does the work in FIRST day and in 3rd day he takes the help of B, C. So 1st A's 2daz work is calculated.
Because A alone does the work in FIRST day and in 3rd day he takes the help of B, C. So 1st A's 2daz work is calculated.
Naari said:
1 decade ago
@vikas.
Good work dude.
Good work dude.
Sindhuja said:
1 decade ago
@monoj.
Superb explanation.
Superb explanation.
Emmanuel said:
1 decade ago
Can someone help me out? why are they multiplying 3 and 5 but not any number for example 3 and 6 making 18 ?
Raman(UIET,KUK) said:
1 decade ago
Guys check dis out........
as we know A will be assist by B & C every third day, so first two day A will work again
A's 1st day of work = 1/20
A's 2nd day of work = 1/20
(A+B+C)'s 3rd day of work = 1/20+1/30+1/60=1/10
total work of 3 days = 1/20+1/20+1/10=1/5
hence,
3 days of work = 1/5
1 day of work will be=1/5*3
=1/15
so work will complete in 15 days
as we know A will be assist by B & C every third day, so first two day A will work again
A's 1st day of work = 1/20
A's 2nd day of work = 1/20
(A+B+C)'s 3rd day of work = 1/20+1/30+1/60=1/10
total work of 3 days = 1/20+1/20+1/10=1/5
hence,
3 days of work = 1/5
1 day of work will be=1/5*3
=1/15
so work will complete in 15 days
(1)
Sai said:
1 decade ago
I still can't get clarification.
In the question they asked that in every 3rd day of A's work.
But in explanation how can you say for only 3 days.
In the question they asked that in every 3rd day of A's work.
But in explanation how can you say for only 3 days.
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