Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 13)
13.
A and B can together finish a work 30 days. They worked together for 20 days and then B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the work?
Answer: Option
Explanation:
| (A + B)'s 20 day's work = |  |
1 | x 20 |  |
= | 2 | . |
| 30 | 3 |
| Remaining work = | |
1 - | 2 | |
= | 1 | . |
| 3 | 3 |
| Now, | 1 | work is done by A in 20 days. |
| 3 |
Therefore, the whole work will be done by A in (20 x 3) = 60 days.
Discussion:
63 comments Page 3 of 7.
RaghavendrA naik said:
6 years ago
A and B should take 30 days completely to finish.
And they finished 20 days work.
20/30 work is over.
10/30=1/3 work remaining.
That work completed by 20days by A.
20*3=60 days required.
And they finished 20 days work.
20/30 work is over.
10/30=1/3 work remaining.
That work completed by 20days by A.
20*3=60 days required.
Srj Jaiswal said:
6 years ago
Hello,
A+b = 60/30 =>2
B=60/20 =>3
60 is total work.
A+b=2,
A+3=2,
A=1.
So, A divided total work.
A=60/1.
= 60ans.
A+b = 60/30 =>2
B=60/20 =>3
60 is total work.
A+b=2,
A+3=2,
A=1.
So, A divided total work.
A=60/1.
= 60ans.
(1)
Tarun said:
6 years ago
The work completed by A&B in one day is,
1/A + 1/B = 1/30 ---> (1)
(1/A + 1/B) * 20 + 1/A * 20 = 1 ---> (2)
Substitute the value of equation (1) in equation (2),
20/30 + 20/A = 1,
20/A = 10/30,
1/A = 1/60.
So, A alone can finish work in 60 days.
1/A + 1/B = 1/30 ---> (1)
(1/A + 1/B) * 20 + 1/A * 20 = 1 ---> (2)
Substitute the value of equation (1) in equation (2),
20/30 + 20/A = 1,
20/A = 10/30,
1/A = 1/60.
So, A alone can finish work in 60 days.
Harsimran kaur said:
7 years ago
@Pankaj.
Total time taken by B is 60 days.
Total time taken by B is 60 days.
Raju said:
8 years ago
A, B, and C working togather can finish cerain piece of work in 40 days. If A and B work together then take 1/3 less time than that of C takes alone. If A andBC work together than they take 1/4 less time than that B takes alone. In how many days B and C working together will finish the work? Can anyone solve this?
Sanjana said:
8 years ago
To make the last step easy we can understand it as follows:
1/3work can be done in 20 days.
So, 1 wor will be don win 20 * 3 60 days (try using direct proportion)
1/3work can be done in 20 days.
So, 1 wor will be don win 20 * 3 60 days (try using direct proportion)
PANKAJ PARIHAR said:
8 years ago
What is the total time taken by B? Please answer it.
E ABHILASH GOWD said:
8 years ago
A+B =30 DAYS.
B LEFT 20 DAYS.
A FINSH WORK IN 20 DAYS.
1-1/20 =19/20.
1/30-19/20 =1/60.
60 DAYS.
B LEFT 20 DAYS.
A FINSH WORK IN 20 DAYS.
1-1/20 =19/20.
1/30-19/20 =1/60.
60 DAYS.
Foram Rana said:
8 years ago
Nice explanation @Harish.
Rohit said:
8 years ago
In how many days B will complete the same work?
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