Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 23)
23.
A and B can do a piece of work in 30 days, while B and C can do the same work in 24 days and C and A in 20 days. They all work together for 10 days when B and C leave. How many days more will A take to finish the work?
Answer: Option
Explanation:
| 2(A + B + C)'s 1 day's work = |  |
1 | + | 1 | + | 1 |  |
= | 15 | = | 1 | . |
| 30 | 24 | 20 | 120 | 8 |
| Therefore, (A + B + C)'s 1 day's work = | 1 | = | 1 | . |
| 2 x 8 | 16 |
| Work done by A, B, C in 10 days = | 10 | = | 5 | . |
| 16 | 8 |
| Remaining work = | |
1 - | 5 | |
= | 3 | . |
| 8 | 8 |
| A's 1 day's work = | |
1 | - | 1 | |
= | 1 | . |
| 16 | 24 | 48 |
| Now, | 1 | work is done by A in 1 day. |
| 48 |
| So, | 3 | work will be done by A in | |
48 x | 3 | |
= 18 days. |
| 8 | 8 |
Discussion:
61 comments Page 3 of 7.
Amar said:
9 years ago
From where do we get 120?
Can anyone explain?
Can anyone explain?
Lavanya said:
9 years ago
I am not understanding how they work 10 days?
Please explain it.
Please explain it.
Shanmugam said:
9 years ago
2( A+B+C) = 15 units.
A+B+C = 7.5 units.
I can't understand this equation @Nikhil.
A+B+C = 7.5 units.
I can't understand this equation @Nikhil.
Rahul R said:
9 years ago
Thanks, @Nikhil. It's very useful to me.
Gobind Mandal said:
9 years ago
Can anyone please explain m,e that how did you multiply by 48?
3/8 * 48?
3/8 * 48?
Dharmendra kushwaha said:
9 years ago
@Suji.
Your explanation clears my doubt, Thank you.
Your explanation clears my doubt, Thank you.
Vipin said:
9 years ago
@Bikash.
Brilliant way, keep it up.
Brilliant way, keep it up.
Vinoth said:
9 years ago
From the very first statement, we can calculate,
A's one day work as 1/60 i.e. (1/30) *(1/2). But they have done some confused calculations and saying that A's 1-day work is 1/48 this is not possible.
The ANSWER IS 22 + 1/2 days.
You all just check it by putting (10days A + B + C work ) + (22 + 1/2 days A's work alone) = 1. Then, you will get 1 which is the total work done
A's one day work as 1/60 i.e. (1/30) *(1/2). But they have done some confused calculations and saying that A's 1-day work is 1/48 this is not possible.
The ANSWER IS 22 + 1/2 days.
You all just check it by putting (10days A + B + C work ) + (22 + 1/2 days A's work alone) = 1. Then, you will get 1 which is the total work done
Gautham Raj said:
9 years ago
I can't understand this, please someone help me.
Kamal said:
9 years ago
How 2 comes in the first step?
I can't get it. Explain me clearly.
I can't get it. Explain me clearly.
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