Time and Work Questions

Time and Work is the most common section in SSC and State PSC Exam Question Papers.

If you are seriously preparing for competitive examinations, you cannot complete your preparation without covering the questions in Time and Work.

If you go through the previous SSC and PSC question papers, you can find at least one question from this category.

Though the questions may look tough, you can answer every question that falls under the category of Time and Work with preparation.

This tutorial will help you learn everything about Time and Work problems. We will teach you all Time and Work formulas to help you solve the questions immediately.

The first part of this guide covers the concepts. The second part covers frequently asked SSC and PSC questions in the Work and Time category.

Those who are preparing for various government jobs through SSC, PSC, and UPSC may find this guide helpful.

Time and Work - Important Formulas

If a man completes his work in 'n' days, work done by him in one day is 1/n.
If the work done by a man in one day is 1/n, he can finish the complete work in n days.
Time and work are always inversely proportional to each other.
If M1 persons can do W1 work in D1 days and M2 persons can do W2 work in D2 days, the general formula to find the total work or total time is :

M1 * D1 * W2 = M2 * D2 * W1

The above concepts are important to solve problems in Time and Work aptitude questions. Now let us check how to solve these questions using shortcuts.

Time & Work - Solved Examples

A can finish a specific work in 10 days and B can do the same in 20 days. Find the time required to complete the work by both A and B together.

Ans:
Work done in a day by A = 1/(10)

Work done by B in a day = 1/(20)

Work done in a day by both A and B together = 1/(10) + 1/(20) = (2 + 1)/(20) =3/20

{ Here, we took the LCM of both denominators. To learn more about it, click the link below.

Apply the first law explained in this tutorial. Time and work are inversely proportional to each other.

=> reverse of 3/20 => 20/3 days
40 persons make 60 bricks in 3 hours. If 8 persons leave the work, how many bricks will be made by the remaining persons in the next 6 hours?

Ans:
Here we need to use the formula M1 * D1 * W2 = M2 * D2 * W1

Here M1 = 40 M2= 32 W1 = 60 D1= 3 D2= 6 W2 = ?
```
   
        
  
          M2  * D2 * W1
  
  w2 =   ------------------
  
          M1 * D1
```
=> W2 = (32 * 6 * 60)/ (40 *3) = 96 bricks
If X can do a piece of work in 25 days, and Y can finish it in 20 days. They worked together for 5 days and then X left. How many days Y will take to complete the work?

Ans:
Work was done by X in a day = 1/25

Work was done by Y in a day =1/20

Work done by both X and Y in 5 days = 5 * (1/25 + 1/20) = 9/20

Remaining work = 1 - (9/20) =11/20

Y finish 1/20 work in a day. So to finish 11/20 work, Y needs 11 more days.

Search This Blog