Introduction
Technically Work is the quantity of energy transferred from one system to another but for question based on this topic, Work is defined as the amount of job assigned or the amount of job actually done.

Formula
- If a Person do a piece of work or job in n days, then person’s finish the work in n days.
- If a Person do a piece of work or job in n days, then work in 1 days = 1 / n.
- If a Person work in 1 days = 1 / n, then person can completed the work in n day’s.
- If a person A done twice work of another person B, then the ratio of work done by A and B is = 2 : 1.
Note: When more people working on a similar type of work, then there group work = Sum of each person 1 day’s work.
Suppose P, Q, R work same piece of work by each person ( P + Q + R )”s 1 day’s work = P’s 1 day’s work + Q’s 1 day’s work + R’s 1 day’s work.
Solved Examples
Question for Tips & Tricks: Time & Work
Try yourself:
A and B alone can do a piece of wok in 8 and 18 days respectively. In how many days the work will be completed if they both work on alternate days starting with B?
Explanation
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Question for Tips & Tricks: Time & Work
Try yourself:
A, B and C can all together do piece of work in 10 days, in which B takes three times as long as A and C together do the work and C takes twice as long as A and B together take to do the work. In how many days B can alone do the work?
Explanation
(A+C) in x days so B completes in 3x days
then (1/x) + (1/3x) = 1/10
solve, x = 40/3
so B in 3x = 3*(40/3)= 40 days
OR
Given A+B+C = 10 and that B takes 3 times as A+C, so A+C is three times stronger than B
So this means that 4 times stronger can do work in 10 days
So 1 time stronger(B) in 4*10 = 40 days
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Question for Tips & Tricks: Time & Work
Try yourself:
20 men can complete a piece of work in 14 days. 7 men started the work and after 20 days, 7 more men joined the work. In how many days the remaining work will be completed?
Explanation
Let (7+7) complete remaining work in x days.
So 20*14 = 7*20 + 14*x
x = 10 days
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