Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 7)
7.
A can do a piece of work in 4 hours; B and C together can do it in 3 hours, while A and C together can do it in 2 hours. How long will B alone take to do it?
Answer: Option
Explanation:
| A's 1 hour's work = | 1 | ; |
| 4 |
| (B + C)'s 1 hour's work = | 1 | ; |
| 3 |
| (A + C)'s 1 hour's work = | 1 | . |
| 2 |
| (A + B + C)'s 1 hour's work = |  |
1 | + | 1 |  |
= | 7 | . |
| 4 | 3 | 12 |
| B's 1 hour's work = | |
7 | - | 1 | |
= | 1 | . |
| 12 | 2 | 12 |
B alone will take 12 hours to do the work.
Discussion:
97 comments Page 9 of 10.
Ashish said:
1 decade ago
Good question. Reasoning is difficult for this one.
Arumugam said:
4 years ago
A = 1/4,
A+b = 1/3.
B = 1/3-1/4 = 1/12.
And = 12.
A+b = 1/3.
B = 1/3-1/4 = 1/12.
And = 12.
(6)
Abhin said:
10 years ago
By the way why we are reciprocating 1/12 into 12?
Shree said:
8 years ago
Clear and detailed explanation. Thank you all.
Anjum said:
9 years ago
Thank you everyone for the clear explanation.
Chiru said:
9 years ago
Thank you everyone for the clear explanation.
Mohit said:
1 decade ago
Why its taken 1/4 and 1/3 ? 4 and 3 why not?
Ankita said:
9 years ago
How, 7/12 - 1/2 = 1/12?
Explain this step.
Explain this step.
Paci said:
1 decade ago
How can calculate 7/12 - 1/2 = 1/12?
Don said:
5 years ago
How 7/12 - 1/2 = 1/12? Explain this.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers