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:
359 comments Page 22 of 36.
Nirav said:
1 decade ago
@chaaya:
1/5 work done in no. of days= 3
1 work done in no. of days= ?
so it is 3/(1/5)= 3*5=15
1/5 work done in no. of days= 3
1 work done in no. of days= ?
so it is 3/(1/5)= 3*5=15
Nandha said:
1 decade ago
@Ajit.
A do a work two days independently, so (1/20+1/20) = 1/10 instead of they taken (1/20*2).
A do a work two days independently, so (1/20+1/20) = 1/10 instead of they taken (1/20*2).
Beeribrahim said:
2 decades ago
How it is user
Now, 1 work is done in 3 days.
5
Whole work will be done in (3 x 5) = 15 days.
Now, 1 work is done in 3 days.
5
Whole work will be done in (3 x 5) = 15 days.
Neha Sharma said:
1 decade ago
Why you are multiply 3*5? And in third step why 1/10 is taken in two times? Please exlain it?
Rajasekhar said:
2 decades ago
The question does'nt mean to find the 3 days work how we can solve this for 3 days work?.
Trinadh said:
1 decade ago
1/20, 1/30, 1/60.
Add 1/3 to the ends of both B and C.
= 1/20+1/30*3+*1/60*3.
= 1/15.
Add 1/3 to the ends of both B and C.
= 1/20+1/30*3+*1/60*3.
= 1/15.
BINDU said:
1 decade ago
Here 1/5 is calculated considering ABC together but here we have to fine work done by A?
Sindhu said:
1 decade ago
@Baskar
Can you please explain me why do you cross multiply at the end for the answer?
Can you please explain me why do you cross multiply at the end for the answer?
Priti said:
1 decade ago
We have already calculate 1/5 for 3 days. Then why again multiplying by 3? please help.
Manoj said:
1 decade ago
i.e;
3 days =1/5
6 days=2/5
9 days=3/5
12 days=4/5
15 days=5/5(1)==work completed
3 days =1/5
6 days=2/5
9 days=3/5
12 days=4/5
15 days=5/5(1)==work completed
(1)
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