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 |
![]() |
45 | = 22 | 1 | days. |
2 | 2 |
Discussion:
281 comments Page 7 of 29.
Sindhu said:
1 decade ago
HI,
This method I feel to be quiet easier.
A is thrice as good as workman as B.
therfore,
A=3B -(1)
finish a job in 60 days less than B
1/B=60+1/A -(2)
i.e B`s One day work = A`s one day work + 60 days.
Solve (1) & (2)
we will get
A= 90;
From (1)
B=A/3
=> B= 30.
(A+B)`s 1 day work = 1/90+1/30
=2/45
=22 1/2 days
This method I feel to be quiet easier.
A is thrice as good as workman as B.
therfore,
A=3B -(1)
finish a job in 60 days less than B
1/B=60+1/A -(2)
i.e B`s One day work = A`s one day work + 60 days.
Solve (1) & (2)
we will get
A= 90;
From (1)
B=A/3
=> B= 30.
(A+B)`s 1 day work = 1/90+1/30
=2/45
=22 1/2 days
Iyappan said:
1 decade ago
Naveen kumar your explanation is beautiful for me.
Sanchi said:
1 decade ago
Very simple way.
3A=1B
B takes x days.
3 (x-60) =x
3x-x=180
X dats is B=90, A=30.
Now,
1/90+1/30=22. 5.
3A=1B
B takes x days.
3 (x-60) =x
3x-x=180
X dats is B=90, A=30.
Now,
1/90+1/30=22. 5.
Nitin singh parihar said:
1 decade ago
Let B do the work in 'x' days.
So, A will take (x-60) days.
Now, ratio of A:B=1:3 (given in ques).
So, 1/3=x-60/x.
=> x=90 (B's 1 day work).
So, A's work=30 days.
Working together=1/30+1/90.
=45/2 days.
Easy and simple.
So, A will take (x-60) days.
Now, ratio of A:B=1:3 (given in ques).
So, 1/3=x-60/x.
=> x=90 (B's 1 day work).
So, A's work=30 days.
Working together=1/30+1/90.
=45/2 days.
Easy and simple.
Akansha said:
1 decade ago
B takes 3 times more days than A.
i.e. B=3A.
So. B-A=60.
3A-A=60 =>.
A=30.
B=90.
Now calculate 1 day work of A and B.
i.e. B=3A.
So. B-A=60.
3A-A=60 =>.
A=30.
B=90.
Now calculate 1 day work of A and B.
Sunny said:
1 decade ago
A is thrice as good as workman as B means 1:3(Ratio)
Therefore A is able to finish a job in 60 days less than B
So A= 1/60 and B=1/60 .....(Given)
According to the ratio
A=1/60 B=1/3*60 (As we are calculating by days)
So Now A = 1/60 < B = 1/90 (A finishes work less than B)
Working together, they can do it in:
1/A+B = 1/60 + 1/90 (As we are calculating by days))
1/A+B = 2/45
So
A+B = 45/2 Days
Option (B) is the correct ans
Therefore A is able to finish a job in 60 days less than B
So A= 1/60 and B=1/60 .....(Given)
According to the ratio
A=1/60 B=1/3*60 (As we are calculating by days)
So Now A = 1/60 < B = 1/90 (A finishes work less than B)
Working together, they can do it in:
1/A+B = 1/60 + 1/90 (As we are calculating by days))
1/A+B = 2/45
So
A+B = 45/2 Days
Option (B) is the correct ans
Vidya said:
1 decade ago
Can you please solve this using unitary method. Its b'coz I follow that method.
Anji said:
1 decade ago
Let the time taken by A be x days,
then time taken by B will be 3x days.
Given that,
time taken by A to finish the work = time taken by B -60
i.e, x=3x-60
=> x=30.
Therefore, time taken by A to finish the work is 30 days.
so B takes 90 days.
Now ,work done by A & B in 1 day=1/30 + 1/90
=4/90
=2/45
Time taken by A & B to complete the work=45/2 days
=22 1/2 days
then time taken by B will be 3x days.
Given that,
time taken by A to finish the work = time taken by B -60
i.e, x=3x-60
=> x=30.
Therefore, time taken by A to finish the work is 30 days.
so B takes 90 days.
Now ,work done by A & B in 1 day=1/30 + 1/90
=4/90
=2/45
Time taken by A & B to complete the work=45/2 days
=22 1/2 days
SANJEEV said:
1 decade ago
#include<stdio.h>
void main()
{
float a,b;
int c,d;
printf("enter ratio of A : B\n");
scanf("%f",&a);
printf("enter no of days lesser than B by A to complete work\n");
scanf("%f",&b);
c=ab/(a-1);
d=c-b;
printf("no of days to complete work by A and B is %d",(c*d)/(c+d));
}
void main()
{
float a,b;
int c,d;
printf("enter ratio of A : B\n");
scanf("%f",&a);
printf("enter no of days lesser than B by A to complete work\n");
scanf("%f",&b);
c=ab/(a-1);
d=c-b;
printf("no of days to complete work by A and B is %d",(c*d)/(c+d));
}
Prabha said:
1 decade ago
If difference of time 2 days B takes 3 days
Similarly why don't we take difference of time 60 days B takes 60*3 is 180 days. Please explain to me ?
Similarly why don't we take difference of time 60 days B takes 60*3 is 180 days. Please explain to me ?
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