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:
227 comments Page 11 of 23.
Abhishek said:
1 decade ago
A - 16 days | 3 unit/day
L. C. M of (16, 12, 4).
| | = 48.
B - 12 days |4 unit/day|.
| |.
C - ? |x unit/day|.
-------------------------------------------------.
(A+B+C) - 4 days | 12 unit/day |.
So, for C we get (12-3+4) = 5 unit/day.
If C can do 5 unit in 1 day, then 48 unit can be done in 48/5 = 9*3/5 days.
Guys this is the easiest way.
L. C. M of (16, 12, 4).
| | = 48.
B - 12 days |4 unit/day|.
| |.
C - ? |x unit/day|.
-------------------------------------------------.
(A+B+C) - 4 days | 12 unit/day |.
So, for C we get (12-3+4) = 5 unit/day.
If C can do 5 unit in 1 day, then 48 unit can be done in 48/5 = 9*3/5 days.
Guys this is the easiest way.
Onkar Vitthal Dabhole said:
1 decade ago
A very very simple solution than the provided as above.
A can complete a work in 16 days, B can complete the same work in 12 days and with the help of C together if they complete the work in 4 days, so assume total work to be done is 48. (LCM of 16, 12, 4).
Persons A B C | A+B+C.
Days- 16 12x = (48/5) = (9+3/5)4.
Work/day- 3 4 5 12 = 3+4+C.
Hence C = 5.
----------------------------------------------------------------.
Work - 48 48 48 48.
A can complete a work in 16 days, B can complete the same work in 12 days and with the help of C together if they complete the work in 4 days, so assume total work to be done is 48. (LCM of 16, 12, 4).
Persons A B C | A+B+C.
Days- 16 12x = (48/5) = (9+3/5)4.
Work/day- 3 4 5 12 = 3+4+C.
Hence C = 5.
----------------------------------------------------------------.
Work - 48 48 48 48.
Sagar said:
1 decade ago
Anyone explain me what is 5 and 48 in relation to C?
Tamilmani said:
1 decade ago
Please answer sir basic formula applied please.
Lijin said:
1 decade ago
How it possible to write 5/48 to 48/5?
See A can complete a work in n days.
A's 1 day work = 1/n.
So here 1/n = 5/48.
So n = 48/5.
Got it!
See A can complete a work in n days.
A's 1 day work = 1/n.
So here 1/n = 5/48.
So n = 48/5.
Got it!
Khizer said:
1 decade ago
= 1/16+1/12+1/C = 1/4.
C = 48/5.
C = 48/5.
Naresh saini said:
1 decade ago
How it is possible to write 5/48 to 48/5?
Bhavana said:
1 decade ago
Firstly take the LCM.
A B ABC.
16 12 4.
LCM IS 48 then ratio is.
A B ABC.
3 4 12.
If a+b-ABC then it's find the value of C = 5 total is 48.
Then divide the 48/5 so simple.
A B ABC.
16 12 4.
LCM IS 48 then ratio is.
A B ABC.
3 4 12.
If a+b-ABC then it's find the value of C = 5 total is 48.
Then divide the 48/5 so simple.
Helper said:
1 decade ago
We get 1/x=5/48.
Then we want x. So x=48/5.
Then we want x. So x=48/5.
Shivu said:
1 decade ago
Hi thanks all of you solving this problem in easy methods.
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