Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 17)
17.
A is 30% more efficient than B. How much time will they, working together, take to complete a job which A alone could have done in 23 days?
Answer: Option
Explanation:
Ratio of times taken by A and B = 100 : 130 = 10 : 13.
Suppose B takes x days to do the work.
Then, 10 : 13 :: 23 : x  x = |
 |
23 x 13 |  |
x = |
299 | . |
| 10 | 10 |
| A's 1 day's work = | 1 | ; |
| 23 |
| B's 1 day's work = | 10 | . |
| 299 |
| (A + B)'s 1 day's work = | |
1 | + | 10 | |
= | 23 | = | 1 | . |
| 23 | 299 | 299 | 13 |
Therefore, A and B together can complete the work in 13 days.
Discussion:
119 comments Page 11 of 12.
Thilagavathinagarajan said:
7 years ago
Why we consider 10:13::23:x? Please explain this step.
Sajan said:
8 years ago
Thanks @Nishant. Your answer is understandable.
Sajid said:
1 decade ago
299/10 to convert 10/299 why please explain?
Kalai said:
9 years ago
Why can't we use ratio as A:B -> 70:100?
BIKKU said:
7 years ago
a : B = 13 : 10,
13 * 23 = x * 23.
x = 13.
13 * 23 = x * 23.
x = 13.
Manjunatha M S said:
5 years ago
@Prathyusha.
Great, very helpful. Thanks.
Great, very helpful. Thanks.
(1)
Amit said:
9 years ago
We have to take 130:100? Why not 100:70?
DHARADI said:
6 years ago
B = (10+13/23)12.
B = (23/23)13,
B = 13.
B = (23/23)13,
B = 13.
Chandradeepa said:
6 years ago
Why should we consider only 100 and 130?
Umesh said:
1 decade ago
@Rahul.
How in 5 days please explain?
How in 5 days please explain?
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