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:
96 comments Page 10 of 10.
ARAVIND MATHALA said:
1 year ago
A = 1/4
B+C = 1/3
A+C = 1/2
B=?
C = (A+C)-A = > (1/2)-1/4 =>1/4,
B = (B+C)-C = >(1/3)-1/4 =>1/12.
Then B = 12 Hours.
B+C = 1/3
A+C = 1/2
B=?
C = (A+C)-A = > (1/2)-1/4 =>1/4,
B = (B+C)-C = >(1/3)-1/4 =>1/12.
Then B = 12 Hours.
(5)
Moustafa Elhosiny said:
1 year ago
A's 1 hour = 1/4,
B+C 1 hour = 1/3,
A+C 1 hour = 1/2.
C = 1/2 - A
C = 1/2 - 1/4 = 1/4.
B+C = 1/3,
Then B = 1/3 -C.
B = 1/3 - 1/4 = 1/12.
So, B can do the work in 12 hours.
B+C 1 hour = 1/3,
A+C 1 hour = 1/2.
C = 1/2 - A
C = 1/2 - 1/4 = 1/4.
B+C = 1/3,
Then B = 1/3 -C.
B = 1/3 - 1/4 = 1/12.
So, B can do the work in 12 hours.
(8)
Kumar Pawar said:
1 year ago
A = 1/4 ---> (1)
B + C = 1/3 ---->(2)
A + C = 1/2---->(3)
Put Equation in (1)in (3)
A + C = 1/2.
1/4 + C = 1/2,
C = 1/2 - 1/4 = 1/4.
C = 1/4.
Put C in equation (2).
B + 1/4 = 1/3
B = 1/3 - 1/4
B = 1/12 Days.
So, the Answer is 12 days.
B + C = 1/3 ---->(2)
A + C = 1/2---->(3)
Put Equation in (1)in (3)
A + C = 1/2.
1/4 + C = 1/2,
C = 1/2 - 1/4 = 1/4.
C = 1/4.
Put C in equation (2).
B + 1/4 = 1/3
B = 1/3 - 1/4
B = 1/12 Days.
So, the Answer is 12 days.
(13)
SUREKHA said:
11 months ago
A = 1/4
B + C = 1/3
A+C = 1/2
B =?
A + (B + C) - (A + C) = 1/4 + 1/3 - 1/2
B = 1/12.
B = 12 DAYS.
B + C = 1/3
A+C = 1/2
B =?
A + (B + C) - (A + C) = 1/4 + 1/3 - 1/2
B = 1/12.
B = 12 DAYS.
(16)
Lakshmi said:
11 months ago
A --->1/4.
A+B -->1/3.
(A+B)-A -->1/3-1/4.
= 1/12.
B alone 12 hours.
A+B -->1/3.
(A+B)-A -->1/3-1/4.
= 1/12.
B alone 12 hours.
(15)
ESNALA SIDDA said:
4 weeks ago
A = 1/4.
B + C = 1/3.
A + C = 1/2.
C = 1/2-1/4.
= 1/4,
B = 1/3 - 1/4.
= 1/12.
=12hrs.
B + C = 1/3.
A + C = 1/2.
C = 1/2-1/4.
= 1/4,
B = 1/3 - 1/4.
= 1/12.
=12hrs.
(1)
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