Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 2)
2.
A can lay railway track between two given stations in 16 days and B can do the same job in 12 days. With help of C, they did the job in 4 days only. Then, C alone can do the job in:
Answer: Option
Explanation:
| (A + B + C)'s 1 day's work = | 1 | , |
| 4 |
| A's 1 day's work = | 1 | , |
| 16 |
| B's 1 day's work = | 1 | . |
| 12 |
 C's 1 day's work = |
1 | - |  |
1 | + | 1 |  |
= | |
1 | - | 7 | |
= | 5 | . |
| 4 | 16 | 12 | 4 | 48 | 48 |
| So, C alone can do the work in | 48 | = 9 | 3 | days. |
| 5 | 5 |
Discussion:
224 comments Page 6 of 23.
Srinivas said:
1 decade ago
If I go for another way as follows:
A B and C can do work in 4days.
A alone 16 days.
B alone 12 days.
C alone ?... Lets assume it as X.
Let me apply this formula
Work done by A B and C put together i.e 4= (16*12*X)/(16+12+X) //(A*B*C)/(A+B+C).
28+X=48X.
28=47X.
X=28/47.
According To you Answer is Wrong How is it. Please Reply me As soon As possible.
A B and C can do work in 4days.
A alone 16 days.
B alone 12 days.
C alone ?... Lets assume it as X.
Let me apply this formula
Work done by A B and C put together i.e 4= (16*12*X)/(16+12+X) //(A*B*C)/(A+B+C).
28+X=48X.
28=47X.
X=28/47.
According To you Answer is Wrong How is it. Please Reply me As soon As possible.
Sonu said:
1 decade ago
Why do we take fraction and add and subtract everything?
Ashim Ray said:
1 decade ago
Why you have shown in the last fraction 48/5 in where the result has come out 5/48?
Manoj Kumar said:
1 decade ago
Why you have shown in the last fraction 48/5 in where the result has come out 5/48? Please explain it.
Leena said:
1 decade ago
One day's work is 5/48.
But we want number of days that 'C' alone can do, so 48/5 days.
But we want number of days that 'C' alone can do, so 48/5 days.
Shakir said:
1 decade ago
We know a formula that,
If A do a work in X days, B do a work in Y days and C do a work in Z days.
Then all of three can do the same work in = XYZ/(XY+YZ+ZX).
Then,
According to question,
A do a work in 16 days,B do the same work in 12 days and let C do the same work in Days
Then we can write as,
(16*12*x)/(16*12+12x+16x) = 4.
And solve it.
If A do a work in X days, B do a work in Y days and C do a work in Z days.
Then all of three can do the same work in = XYZ/(XY+YZ+ZX).
Then,
According to question,
A do a work in 16 days,B do the same work in 12 days and let C do the same work in Days
Then we can write as,
(16*12*x)/(16*12+12x+16x) = 4.
And solve it.
Sunny said:
1 decade ago
How to convert 5/48 = 9*3/5?
Srinivas said:
1 decade ago
C's 1 day work was 5/48. So it can be written as 1/(48/5) and as per the formula if C can do a work in 1/n days then C can complete work in n days which is 48/5. Mixed fraction is written as 9(3/5) = (5*9+3 )/5.
Carlo said:
1 decade ago
1/4 = 1/16 + 1/12 + 1/X.
X = 9.6 days or 9 3/5 days.
X = 9.6 days or 9 3/5 days.
Naseer Mohammad said:
1 decade ago
Why you have shown 48/5 instead of 5/48? Any one can help me.
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