Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 9)
9.
A does 80% of a work in 20 days. He then calls in B and they together finish the remaining work in 3 days. How long B alone would take to do the whole work?
23 days
37 days
37
40 days
Answer: Option
Explanation:
| Whole work is done by A in |  |
20 x | 5 |  |
= 25 days. |
| 4 |
| Now, | |
1 - | 4 | |
i.e., | 1 | work is done by A and B in 3 days. |
| 5 | 5 |
Whole work will be done by A and B in (3 x 5) = 15 days.
| A's 1 day's work = | 1 | , (A + B)'s 1 day's work = | 1 | . |
| 25 | 15 |
 B's 1 day's work = |
|
1 | - | 1 | |
= | 4 | = | 2 | . |
| 15 | 25 | 150 | 75 |
| So, B alone would do the work in | 75 | = 37 | 1 | days. |
| 2 | 2 |
Discussion:
164 comments Page 13 of 17.
Shanmug said:
1 decade ago
@Baskar you have done great job. Just carry on.
(1)
Manjula said:
1 decade ago
Awesome explanation by @Bhaskar and @Rajendra.
Shivaputra said:
6 years ago
@ Rajendra.
Thanks for the clear explanation.
Thanks for the clear explanation.
Rahul Berry said:
9 years ago
Thank you for your valid explanation @Baskar.
Malini said:
1 decade ago
hey pls tell clearly ya its quite confusing
Abu hanif said:
5 years ago
Please, anyone, help me to get it clearly.
Muna sharma said:
9 years ago
How 80/100 can be 5/4? It should be 4/5.
Abica said:
5 years ago
Nice explanation, Thanks @Vikram Sihag.
Umadatla said:
1 decade ago
1/15-1/25 = 2/75.
How you got 5 1/75?
How you got 5 1/75?
Sathyabama said:
8 years ago
Easy to understand it. Thanks @Wilson.
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