Aptitude - Time and Work - Discussion
Each of the questions given below consists of a question followed by three statements. You have to study the question and the statements and decide which of the statement(s) is/are necessary to answer the question.
In how many days can 10 women finish a work? | |||||
I. | 10 men can complete the work in 6 days. | ||||
II. |
| ||||
III. | If 10 men work for 3 days and thereafter 10 women replace them, the remaining work in completed in 4 days. | ||||
I. (10 x 6) men can complete the work in 1 day.
 1 man's 1 day's work = |
1 |
| 60 |
| II. |  |
10 x | 24 |  |
men + | |
10 x | 24 | |
women can complete the work in 1 day. |
| 7 | 7 |
| |
|
240 | |
men's 1 day work + | |
240 | |
women's 1 day work = 1. |
| 7 | 7 |
| |
|
240 | x | 1 | |
+ | |
240 | |
women's 1 day's work = 1. |
| 7 | 60 | 7 |
| |
|
240 | |
women's 1 day's work = | |
1 - | 4 | |
= | 3 |
| 7 | 7 | 7 |
| 10 women's 1 day's work = |
|
3 | x | 7 | x 10 | |
= | 1 |
| 7 | 240 | 8 |
So, 10 women can finish the work in 8 days.
III. (10 men's work for 3 days) + (10 women's work for 4 days) = 1
(10 x 3) men's 1 day's work + (10 x 4) women's 1 day's work = 1
30 men's 1 day's work + 40 women's 1 day's work = 1
Thus, I and III will give us the answer.
And, II and III will give us the answer.
Correct answer is (A).
In the question, they asked 10 women can finish the work in how many days?
1st option it gives only about the men na. How come women days can be obtained?
20 men, 1 day work = 1/10.
20 men, 3 day work = 3/10.
Remaining work = 1 - 3/10 = 7/10.
Now we take 1 men, 1 day work = 1/60,
Now 5 men return back therefore only 15 men will present.
Now 15 men, 1 day work = 15/200.
Therefore to complete remaining 7/10 work number of days are = (7/10) * (200/15) = 28/3 days.
Please help me to answer this.
In your answer to solve 2&3, you are using 1 men's 1-day work = 1/60.
I think this is derived from statement 1. Other statements are not mentioning this. So why this used here in solution?
(10 men + 10 women)'s 1 day work = 7/24.
1/10*6*10 + 10 women = 7/4.
So 10 women's 1 day work = 7/4-1/6 = 3/24 = 1/8.