Question

A man completes a work in 1 hour in his first attempt and in his second attempt he completes it in (1/4) of 1 hour. In his third attempt, he completes it in (4/5)^th time of what he took in his second attempt. How long did he take to complete the work in his third attempt? What is the difference in the time taken by him in the first and third attempt? [3 MARKS]

Answer 1

Steps: [1 Marks]
Each answer: [1 Mark]

Time taken by the man in his first attempt = 1 hour

Time taken by the man in his second attempt = $\frac{1}{4}\times 1$

= $\frac{1}{4}$ hour

Time taken by the man in his third attempt = $\frac{1}{4}\times \frac{4}{5}$

= $\frac{1}{5}$

Hence he took $\frac{1}{5}$ hours to complete the work on his third attempt.

The difference in the time taken by him in his first attempt and third attempt
$=1-\frac{1}{5}=\frac{4}{5}hours$