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:
281 comments Page 3 of 29.
Jagadish Behera said:
3 years ago
"A" is 3 times more than" B" (efficiency)
Difference = 60 days
3x-x = 60
X = 30days This is" B"
A=3 * 30 = 90 days.
So Total work =180
A=2 WORK
B=6 WORK
A+B TOGETHER CAN DO IN 180/8 = 22.5 DAYS.
Difference = 60 days
3x-x = 60
X = 30days This is" B"
A=3 * 30 = 90 days.
So Total work =180
A=2 WORK
B=6 WORK
A+B TOGETHER CAN DO IN 180/8 = 22.5 DAYS.
(14)
Gogo said:
3 years ago
A+B = (1/30 + 1/90) = 2/45.
How we are getting this?
How we are getting this?
(8)
HARINI said:
3 years ago
Given;
A = 3B;
A = B - 60.
Substitute A = 3B in 2nd equation(a=b-60).
3B = B-60
B = 30.
Therefore; A = 3B = 90.
A+B = (1/30 + 1/90) = 2/45.
So, the answer is 22(1/2).
A = 3B;
A = B - 60.
Substitute A = 3B in 2nd equation(a=b-60).
3B = B-60
B = 30.
Therefore; A = 3B = 90.
A+B = (1/30 + 1/90) = 2/45.
So, the answer is 22(1/2).
(24)
Muhammad said:
4 years ago
Let A's total work completion time be = n.
B's total work completion time = 3n,
Difference between B and A's daily work = 60.
3n - n = 60,
2n = 60.
n = 30.
Total daily work.
=1/3n + 1/n,
=1/90 + 1/30,
=2/45,
So total time to complete for both = 45/2 = 22.5.
B's total work completion time = 3n,
Difference between B and A's daily work = 60.
3n - n = 60,
2n = 60.
n = 30.
Total daily work.
=1/3n + 1/n,
=1/90 + 1/30,
=2/45,
So total time to complete for both = 45/2 = 22.5.
(12)
Jeeva said:
4 years ago
a ------ b
x ------ 3x.
1/3 of the work is remaining = 1 - 1/3.
= 2/3.
2/3 of the work is completed by b = 60 days.
one of the work is completed by b = 60 * 3/2.
b = 90.
B one day work = 1/90.
A one-day work = 1/30.
a+b = 1/30 + 1/90.
a+b = 4/90
a+b = 2/45.
A and B together can do the work = 45/2.
x ------ 3x.
1/3 of the work is remaining = 1 - 1/3.
= 2/3.
2/3 of the work is completed by b = 60 days.
one of the work is completed by b = 60 * 3/2.
b = 90.
B one day work = 1/90.
A one-day work = 1/30.
a+b = 1/30 + 1/90.
a+b = 4/90
a+b = 2/45.
A and B together can do the work = 45/2.
(1)
Sachin said:
4 years ago
Thanks everyone.
(1)
Padma said:
4 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)
Srikanth said:
4 years ago
Thanks @Sundhar.
Astik Mandal said:
4 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)
HMJ said:
4 years ago
A=3B,
A can finish the job 60 days less then B,
Say, work=60.
Capacity of B = (60/x) ----> 1
Cap of A = (60/x-60) ----> 2.
As per the condition A=3B.
Compare the above equation by putting the Capacity of A = 3 times Capacity of B.
You will get x=90.
Now put this x in above equations 1 and 2.
You will get the cap of A = 2 and Cap of B = 0.66.
Working together,
Days= Work/(cap of A + cap of B).
= 60/2.66,
= 22.5.
A can finish the job 60 days less then B,
Say, work=60.
Capacity of B = (60/x) ----> 1
Cap of A = (60/x-60) ----> 2.
As per the condition A=3B.
Compare the above equation by putting the Capacity of A = 3 times Capacity of B.
You will get x=90.
Now put this x in above equations 1 and 2.
You will get the cap of A = 2 and Cap of B = 0.66.
Working together,
Days= Work/(cap of A + cap of B).
= 60/2.66,
= 22.5.
(1)
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