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?
8 hours
10 hours
12 hours
24 hours
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

Therefore B alone will take 12 hours to do the work.

Discussion:
95 comments Page 10 of 10.

Sam said:   8 years ago
You explained well @Akshay.

Xyx said:   8 years ago
How it will 7/12-1/2=1/12?
(1)

Spoorti said:   4 years ago
Thank you @Bhanu.
(3)

Sukumar said:   7 years ago
Well said @Hindu.

Shro said:   1 decade ago
Thanku hindu:).


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