Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 13)
13.
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?
Answer: Option
Explanation:
| (A + B)'s 20 day's work = |  |
1 | x 20 |  |
= | 2 | . |
| 30 | 3 |
| Remaining work = | |
1 - | 2 | |
= | 1 | . |
| 3 | 3 |
| Now, | 1 | work is done by A in 20 days. |
| 3 |
Therefore, the whole work will be done by A in (20 x 3) = 60 days.
Discussion:
65 comments Page 7 of 7.
Avi said:
1 decade ago
A & B together works for 30 days
so, (A & B)'s 1 day work= 1/30
A&B worked for 20 days together
it is said after working together for 20 days b left
so, (A&B)'s work for 20 days together = (1/30)x20=2/3
remaining work that is to be done =1-2/3=1/3
1/3 work is done in 20 days
1 work i.e; complete work would be done in 20/(1/3)=20x3=60 days
so, (A & B)'s 1 day work= 1/30
A&B worked for 20 days together
it is said after working together for 20 days b left
so, (A&B)'s work for 20 days together = (1/30)x20=2/3
remaining work that is to be done =1-2/3=1/3
1/3 work is done in 20 days
1 work i.e; complete work would be done in 20/(1/3)=20x3=60 days
Dhruv said:
1 decade ago
How come 1/3 work is done in 20 days should the work in 20 days not be 2/3?
Srishailam said:
1 decade ago
Am not understanding this problem any body please help me.
How A work come 20 days. Explain ?
How A work come 20 days. Explain ?
Asha said:
1 decade ago
Hey @ankush
The question here is that in how many days A alone can do the entire work..
So its very simple 1/3 work done in 20 days, 2/3 work in 20*2=40 days and 3/3 (i.e. 1)= 20*3=60 days.
The question here is that in how many days A alone can do the entire work..
So its very simple 1/3 work done in 20 days, 2/3 work in 20*2=40 days and 3/3 (i.e. 1)= 20*3=60 days.
Ankush said:
1 decade ago
Now, 1 work is done by A in 20 days. 3 Therefore, the whole work will be done by A in (20 x 3) = 60 days.
Please can anyone explain me this.
Please can anyone explain me this.
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