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 11 of 23.
Harmit said:
1 decade ago
Easiest method.
LCM is 48 of 16 &12. Then A can complete work in 3 work and B can 4 work.
Now A B C can complete 12 work.
Now A and B complete 7 work so still remaining work is 5.
So C can alone complete work 48/5. So answer is C. You can easily calculate.
LCM is 48 of 16 &12. Then A can complete work in 3 work and B can 4 work.
Now A B C can complete 12 work.
Now A and B complete 7 work so still remaining work is 5.
So C can alone complete work 48/5. So answer is C. You can easily calculate.
Sasmita said:
1 decade ago
Tell me any one that c's work. I can't understand it.
GAUTAM said:
1 decade ago
Answer of C work 5/48 to 48/5.
This is one day work of C.
Example as given in question itself.
A work complete in 16 day so in 1 day 'a' will complete 1/16 portion of whole work. Whole work completed by a is 16/1=16 days.
This is one day work of C.
Example as given in question itself.
A work complete in 16 day so in 1 day 'a' will complete 1/16 portion of whole work. Whole work completed by a is 16/1=16 days.
Naresh said:
1 decade ago
How do you get 1/4?
Pundir said:
1 decade ago
All the explanations are really amazing and understandable. But I would like to add a point to the discussion. Why did we do 1/16, 1/12 or 1/4. See there is lot frequency distribution in the values. So to ease our lives we want to compare all this to a benchmark value.
In this case everybody is taking different number of duration's to complete a particular task. So first we want to find out how much work everybody was able to complete in any particular day. Just to make the calculations easier.
And if one can do (1/16)th part of a work in one day, then just by reversing the fraction we can get to know in total how many days he/she will be able to complete the entire task.
Hope this will help.
In this case everybody is taking different number of duration's to complete a particular task. So first we want to find out how much work everybody was able to complete in any particular day. Just to make the calculations easier.
And if one can do (1/16)th part of a work in one day, then just by reversing the fraction we can get to know in total how many days he/she will be able to complete the entire task.
Hope this will help.
Mahesh sawant said:
1 decade ago
Please explain how come 5/48?
Mohammed aqib said:
1 decade ago
In equation 5/48 how did 5 arise?
Anurag said:
1 decade ago
Can anybody explain LCM method like this?
Lets see this simple method,
LCM of 16 and 12 is 48.
So A and B will finish their work in 3 and 4 hr.
Answer C will finish in 12 hr.
Hence 12-(3+4) = 5 hr.
Hence answer is 48/5.
Lets see this simple method,
LCM of 16 and 12 is 48.
So A and B will finish their work in 3 and 4 hr.
Answer C will finish in 12 hr.
Hence 12-(3+4) = 5 hr.
Hence answer is 48/5.
Ayush said:
1 decade ago
Can anybody explain the basic to know how the 48/5 comes?
Phani Kumar said:
1 decade ago
Can explain 5/48 has come?
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