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 6 of 7.
Shail said:
1 decade ago
@Aditya.
Because a+b.
b+c.
c+a.
So we take out common 2 in the beginning. Got it dear.
Because a+b.
b+c.
c+a.
So we take out common 2 in the beginning. Got it dear.
Hanumant said:
1 decade ago
I am not understanding how to calculate 1/48.7/240.1/80?
Varsha said:
1 decade ago
How did you calculated A's work for 1 day when we do not know any individual work for 1 day?
Sajal said:
10 years ago
I want to ask that why we have solved the equations at the top?
Pooja said:
10 years ago
How to add fractions like the above one in the questions? I am not getting 15/120 please explain.
Pooja said:
10 years ago
How to solve fractions like 1/30+ 1/24+1/20? Please someone explain in details I am not getting 15/120 as answer please.
Pari said:
10 years ago
Why we take 1/24, from where its comes?
Kishore said:
1 decade ago
Why shld we consider 2(a+b+c) at first ?
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.
Gautham Raj said:
9 years ago
I can't understand this, please someone help me.
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