Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 1)
1.
A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is :
Answer: Option
Explanation:
| A's 1 day's work = | 1 | ; |
| 15 |
| B's 1 day's work = | 1 | ; |
| 20 |
| (A + B)'s 1 day's work = |  |
1 | + | 1 |  |
= | 7 | . |
| 15 | 20 | 60 |
| (A + B)'s 4 day's work = | |
7 | x 4 | |
= | 7 | . |
| 60 | 15 |
| Therefore, Remaining work = | |
1 - | 7 | |
= | 8 | . |
| 15 | 15 |
Discussion:
344 comments Page 11 of 35.
Atma kumar vishwakarma said:
8 years ago
Let both making toffee.
The total toffee they made is 60 it LCM of 20 and15.
mins A make 60 toffee in 15 days it mins A make 4 toffee a day,
B makes 60 toffee in 20 days it mins B make 3 toffy a day they work together for day
it mins (3+4)*4=28.
In 4 days they made 28 toffee they need to make 60 toffee.
It mins 28/60=7/15.
The total toffee they made is 60 it LCM of 20 and15.
mins A make 60 toffee in 15 days it mins A make 4 toffee a day,
B makes 60 toffee in 20 days it mins B make 3 toffy a day they work together for day
it mins (3+4)*4=28.
In 4 days they made 28 toffee they need to make 60 toffee.
It mins 28/60=7/15.
Sneha said:
8 years ago
Therefore, A + B + C = 36w/13d/w=2*10/13. How is it? please explain.
Dhananjay Moundekar said:
8 years ago
@Prabhu.
6d/w <= A---->6d
4d/w <= B---->9d
3d/w <= C----->12d
Total Work is LCM of A,B,C =36W
They All do toghether means,
A+B+C=>6+4+3=13d/w
Therefore, A + B + C = 36w/13d/w=2*10/13.
6d/w <= A---->6d
4d/w <= B---->9d
3d/w <= C----->12d
Total Work is LCM of A,B,C =36W
They All do toghether means,
A+B+C=>6+4+3=13d/w
Therefore, A + B + C = 36w/13d/w=2*10/13.
Prabhu said:
8 years ago
Can anyone solve this?
Problem: 'A' can do a piece of in 6days, 'B' in 9days and 'C' in 12 days. In how many days will all of the together finish the work?
Problem: 'A' can do a piece of in 6days, 'B' in 9days and 'C' in 12 days. In how many days will all of the together finish the work?
Karthik said:
8 years ago
How comes 300 please explain?
Asi ganesh said:
8 years ago
Why sub (1-7/15)?
I can explain
7/15 is A, B are together work in 4 days
Then question is remaining work is nothing but left this work is total work is 1 and remaining work is is nothing but all of you know
(1-7/15)=8/15.
I can explain
7/15 is A, B are together work in 4 days
Then question is remaining work is nothing but left this work is total work is 1 and remaining work is is nothing but all of you know
(1-7/15)=8/15.
Shiva said:
8 years ago
Why sub (1-7/15)? please explain.
Jenifer said:
8 years ago
@Shubam Mishra.
Because 60 is just the value of L.C.M.
Because 60 is just the value of L.C.M.
NISHA said:
8 years ago
Why sub this (1-7/15) can you explain?
Shubham mishra said:
8 years ago
@Ankit kain.
In the last step why you take 28/60 instead of 60/28?
In the last step why you take 28/60 instead of 60/28?
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