Time and Work Examples 1

In this class, We discuss Time and Work Examples 1.

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The reader should have prior knowledge of Time and work ratio examples. Click Here.

The examples will help you understand how they ask the questions.

Example 1:

A and B, working separately, can do work in 9 and 12 days, respectively.

If they work alternately, starting with A. In how many days will the work be completed?

Solution:

A’s one-day work is 1/9

B’s one-day work is 1/12

They work alternate days. so (A+B)’s 2 days work = 1/9 + 1/12 = 7/36.

Work done in 5 pair of days = 5 * 7/36 = 35/36.

Remaining work = 1 – 35/36 = 1/36.

On the 11th day, it’s A’s turn.

1/36 of the work is done by A in 9 * 1/36 = 1/4.

Total 10 1/4 days.

Example 2:

Forty-five men can complete work in 16 days.

Six days after they started working, 30 more men joined them.

How many days will they take to complete the remaining work?

Solution:

Important: Identifying one mans one day work is needed.

Forty-five men one day work is 1/16.

(45 * 16) men can complete the work in 1 day.

Seven hundred twenty men can complete the work in 0ne day.

One man, one-day work = 1/720.

45 men’s 6 days work = 6 * 1/16 = 3/8

Remaining work = 1- 3/8 = 5/8

Seventy-five men one day’s work = 75/720.

In one day, The work done = 5/48.

The days to complete 5/8 of the work = (5/8)/(5/48).

= 6 days.