Question

a man and a boy finish a certain piece of work in 20 days whereas a man alone can do it in 25 days .it is found that the man does the work x times as fast as the boy .find x?

Answer 1

x = 4 is the answer.

Step-by-step explanation:

Let a man completes the work alone in days = a = 25

Per day work done by a man = $\frac{1}{a}$ = $\frac{1}{25}$

Let a boy can finish the work in the duration = b days

Per day work done by a boy = $\frac{1}{b}$

It is given that man does the work x times as fast as the boy.

Therefore, $\frac{1}{a}=x\times \frac{1}{b}$

b = ax -------(1)

A man and a boy finish a certain piece of work in duration = 20 days

per day work done by both together = $\frac{1}{20}$

$\frac{1}{a}+\frac{1}{b}=\frac{1}{20}$

$\frac{a+b}{ab}=\frac{1}{20}$

From equation (1),

$\frac{a+ax}{a(ax)}=\frac{1}{20}$

20(1 + x) = ax

20(1 + x) = 25x [Since a = 25]

20 + 20x = 25x

5x = 20

x = 4

Practice similar problems from https://brainly.in/question/9425553

Answer 2

Answer:

4 is answer of question