Aptitude - Time and Work - Discussion
Discussion Forum : Time and Work - General Questions (Q.No. 4)
4.
A is thrice as good as workman as B and therefore is able to finish a job in 60 days less than B. Working together, they can do it in:
Answer: Option
Explanation:
Ratio of times taken by A and B = 1 : 3.
The time difference is (3 - 1) 2 days while B take 3 days and A takes 1 day.
If difference of time is 2 days, B takes 3 days.
| If difference of time is 60 days, B takes |  |
3 | x 60 |  |
= 90 days. |
| 2 |
So, A takes 30 days to do the work.
| A's 1 day's work = | 1 |
| 30 |
| B's 1 day's work = | 1 |
| 90 |
| (A + B)'s 1 day's work = | |
1 | + | 1 | |
= | 4 | = | 2 |
| 30 | 90 | 90 | 45 |
 A and B together can do the work in |
45 | = 22 | 1 | days. |
| 2 | 2 |
Discussion:
293 comments Page 4 of 30.
Yash Sangle said:
1 year ago
3/1 = (B)/(B-60).
As work done and time are inversely related,
So, B=90, A=30.
(1/90 + 1/30) = (2/45),
So, 22 1/5.
As work done and time are inversely related,
So, B=90, A=30.
(1/90 + 1/30) = (2/45),
So, 22 1/5.
(5)
Vishakha said:
6 months ago
According to me, it is 20 days.
(5)
Astik Mandal said:
5 years ago
A - 30d.
B - 90d.
lcm - 90(total work).
Efficiency of A - 3.
Efficiency of B - 1.
Total Efficiency = 4 total.
work/totalEfficiency=90/4=22.5.
B - 90d.
lcm - 90(total work).
Efficiency of A - 3.
Efficiency of B - 1.
Total Efficiency = 4 total.
work/totalEfficiency=90/4=22.5.
(4)
Padma said:
5 years ago
Here a simple calculation is;
A takes 1 part and B takes 3 parts.
\
So A:B ratio is 1:3.
total 4p.and the difference is 2,they did work in 60 days so 60p.
4p=60.
p=15/1.
B total working days 15*3=45.
W/t is 45/2.
A takes 1 part and B takes 3 parts.
\
So A:B ratio is 1:3.
total 4p.and the difference is 2,they did work in 60 days so 60p.
4p=60.
p=15/1.
B total working days 15*3=45.
W/t is 45/2.
(4)
Shweta pal said:
5 months ago
Why we have to take work of A=x it should be 3x?
Can anyone explain?
Can anyone explain?
(3)
Sundar said:
2 decades ago
@All (Must read if you have any doubts)
If B takes 3 days then A takes 1 day to complete the task.
Time taken Ratio => A : B = 1 day : 3 days.
1 3 (difference is 2)
10 30 (diff 20)
30 90 (diff 60) <= Here diff is 60 days, So this is the correct ratio to be used in calculation, since it was mentioned in the given question.
A alone can finish the task in 30 days.
B alone can finish the task in 90 days.
Work done by A alone in 1 day = 1/30
Work done by B alone in 1 day = 1/90
Work done by A and B in one day (1/30 + 1/90) = 3+1/90 = 4/90
The no. of days required to complete the task by A and B is
= 90/4
= 22.5 days.
////**** Important Note: ****////
We cannot take other ratios like 1:3, 10:30, 40:120, 60:180 for the calculation. Since the diff is mentioned as 60 days.
Because, it will give different answers for each different ratios used for calculation.
If we take 1:3 => (1/1 + 1/3) = 4/3
If we take 10:30 => (1/10 + 1/30) = 4/30
If we take 40:120 = (1/40 + 1/120) = 4/120
If we take 60:180 => (1/60 + 1/180) = 4/180 ... so on.
I hope this will help you. Have a nice day!
If B takes 3 days then A takes 1 day to complete the task.
Time taken Ratio => A : B = 1 day : 3 days.
1 3 (difference is 2)
10 30 (diff 20)
30 90 (diff 60) <= Here diff is 60 days, So this is the correct ratio to be used in calculation, since it was mentioned in the given question.
A alone can finish the task in 30 days.
B alone can finish the task in 90 days.
Work done by A alone in 1 day = 1/30
Work done by B alone in 1 day = 1/90
Work done by A and B in one day (1/30 + 1/90) = 3+1/90 = 4/90
The no. of days required to complete the task by A and B is
= 90/4
= 22.5 days.
////**** Important Note: ****////
We cannot take other ratios like 1:3, 10:30, 40:120, 60:180 for the calculation. Since the diff is mentioned as 60 days.
Because, it will give different answers for each different ratios used for calculation.
If we take 1:3 => (1/1 + 1/3) = 4/3
If we take 10:30 => (1/10 + 1/30) = 4/30
If we take 40:120 = (1/40 + 1/120) = 4/120
If we take 60:180 => (1/60 + 1/180) = 4/180 ... so on.
I hope this will help you. Have a nice day!
(2)
Anom said:
4 months ago
How 30 days taken? Please explain me.
(2)
Rajender said:
2 decades ago
Please tell me how you have calculated differece of time 2 days.
(1)
Sundar said:
2 decades ago
Hi Friends!
The statement "A is thrice as good as workman as B" states that, If A complete a work in 1 day, B will take 3 days to complete the same work.
Therefore, if A takes 1 day, B takes 3 days, the time difference is 2 days.
If the time difference is 2 days, B takes 3 days to complete the work.
Similarly if the time difference is 60 days, then B takes (3/2*60) = 90 days.
Then A takes 90 - 60 = 30 days to complete the work.
It is very simple man.
The statement "A is thrice as good as workman as B" states that, If A complete a work in 1 day, B will take 3 days to complete the same work.
Therefore, if A takes 1 day, B takes 3 days, the time difference is 2 days.
If the time difference is 2 days, B takes 3 days to complete the work.
Similarly if the time difference is 60 days, then B takes (3/2*60) = 90 days.
Then A takes 90 - 60 = 30 days to complete the work.
It is very simple man.
(1)
Indhu said:
2 decades ago
Hi friends,.
Though content is big it is easy to understand.
Work done by A as compared to B=3:1.
Time taken by A as compared to B=1:3.
So, time difference is 2.
A will finish the work 60 days lesser than B.
Therefore time difference is 60.
Time taken for A = 60/2 = 30.
Hence time taken for B=3* time taken by A = 90.
If A+B can do a piece of work in n days, then (A+B) 's 1day's work=1/n.
Working together (A+B) 's one day work = (1/30) + (1/90) =2/45.
If (A+B) 's 1day's work=1/n, then A+B can finish the work in n days.
Therefore total time taken = 45/2= 22. 5 Days.
Though content is big it is easy to understand.
Work done by A as compared to B=3:1.
Time taken by A as compared to B=1:3.
So, time difference is 2.
A will finish the work 60 days lesser than B.
Therefore time difference is 60.
Time taken for A = 60/2 = 30.
Hence time taken for B=3* time taken by A = 90.
If A+B can do a piece of work in n days, then (A+B) 's 1day's work=1/n.
Working together (A+B) 's one day work = (1/30) + (1/90) =2/45.
If (A+B) 's 1day's work=1/n, then A+B can finish the work in n days.
Therefore total time taken = 45/2= 22. 5 Days.
(1)
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