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:
20 days
22 1 days
2
25 days
30 days
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 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.
(14)

Yash Sangle said:   9 months 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.
(13)

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.
(12)

Logesh said:   2 years ago
Finding the days for B and A:

The ratio difference is 2 and the day difference is 60.

So, for every single inc in ratio, it will increase by 30 days.

From this, we can say that A is 30 days and B is 90 days (1:3 time ratio).
(10)

Nikitha Mekala said:   4 weeks ago
A : B is x : 3x.
A takes 60days less than B
So, 3x - x = 60.
X = 30.
Now Ais 30 and Bis 90.
Then the total work is 1/30 + 1/90
= 4/90 ==> 2/45.
So the answer ==> 45/2.
=> 22 1/2.
(9)

Gogo said:   4 years ago
A+B = (1/30 + 1/90) = 2/45.

How we are getting this?
(8)

Yash talavatkar said:   2 weeks ago
A is thrice of B and A takes 60 days less than B.
So,
Assume A takes - 30 days.
B takes - 90 Days.
One day's work of A- 1/30.
One day's work of B - 1 /90.
LCM = 90.
3/90 + 1/90 = 4/90.
90/4 = 22.5.
(6)

Nallapu Rishith Reddy said:   9 months 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.
(5)

Yash Sangle said:   9 months 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.
(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.
(4)


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