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:
287 comments Page 24 of 29.
Raman(UIET,KUK) said:
1 decade ago
Guys check this out and don't be confused....
as we know A is 3 time better than B and A takes 60 days less than B so, time taken by A: time taken by B= 1:3
= b-60:b ( suppose time by B is b)
by cross multiply, 3b-180=b
i.e. b=90 so time taken by B=90
and time taken by the A is=90-60= 30
as we know A is 3 time better than B and A takes 60 days less than B so, time taken by A: time taken by B= 1:3
= b-60:b ( suppose time by B is b)
by cross multiply, 3b-180=b
i.e. b=90 so time taken by B=90
and time taken by the A is=90-60= 30
Aarush said:
1 decade ago
Thanks sheetal.
Varma said:
1 decade ago
Nice formula @Sheetal.
Sureshkumar said:
1 decade ago
Another easy way 2 find out:
1st put the ratio i.e.1:3(A:B)
2nd the condition given here is A can work less than 60 days
So, find out the probability that matches with the ratio condition(A&B must be difference 60 here) for eg:let we take as A as 20 therefore B must be 60(here we get the difference as 40 only)according to 1:3 which cant satisfy
The given condition(A less than B by 60 days) suppose you take A as 30 means you get B as 90 which is greater than 60 days
of A....A=30 B=90 A's 1 day work=1/30
B's 1 day work=1/90 A+B's 1 day work =1/30+1/90=4/90 here they are not given to find out as 1day work...so take as 90/4=22.5 <==> 22(1/2).
1st put the ratio i.e.1:3(A:B)
2nd the condition given here is A can work less than 60 days
So, find out the probability that matches with the ratio condition(A&B must be difference 60 here) for eg:let we take as A as 20 therefore B must be 60(here we get the difference as 40 only)according to 1:3 which cant satisfy
The given condition(A less than B by 60 days) suppose you take A as 30 means you get B as 90 which is greater than 60 days
of A....A=30 B=90 A's 1 day work=1/30
B's 1 day work=1/90 A+B's 1 day work =1/30+1/90=4/90 here they are not given to find out as 1day work...so take as 90/4=22.5 <==> 22(1/2).
Abhay said:
1 decade ago
@Neeraj-A will finish the work 60 days lesser than B,means if B takes 60 days to complete the work,A takes 1 day.
Neeraj said:
1 decade ago
A will finish the work 60 days lesser than B.
What is it mean please explain?
What is it mean please explain?
Gauarv said:
1 decade ago
Thanks harsha.
Brajesh Anuragi said:
1 decade ago
Thanks Showry for given the simple and correct ans.
Anu said:
1 decade ago
Awesome explanation HARSHA
Riyaz said:
1 decade ago
Ratio of times taken by A and B = 1 : 3.
That is If A takes 1 day B takes 3 days
Time Difference is 3-1 = 2 days
Here is the tricky part :
If A takes 1/2 day B takes 3/2 days
Time Difference is 3/2 - 1/2 = 1 days
When time difference is 60 days (Just mulitply by 60)
A takes 60/2 and B takes 3*60/2
So, A takes 30 days to do the work.
and B takes 90 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 = (1/30 + 1/90)= 4/90 = 2/45
A and B together can do the work in 45/2 = 22+1/2
That is If A takes 1 day B takes 3 days
Time Difference is 3-1 = 2 days
Here is the tricky part :
If A takes 1/2 day B takes 3/2 days
Time Difference is 3/2 - 1/2 = 1 days
When time difference is 60 days (Just mulitply by 60)
A takes 60/2 and B takes 3*60/2
So, A takes 30 days to do the work.
and B takes 90 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 = (1/30 + 1/90)= 4/90 = 2/45
A and B together can do the work in 45/2 = 22+1/2
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A and B together can do the work in