Question

A boy goes to school at a speed of 5 kmph and returns to the village at a speed of 4 kmph. If he takes 9 hours in total, find the distance between the village and school​

Answer 1

answer will be 20

let the distance be x

Answer 2

Answer:

$\displaystyle{x=20 \ \text{km}}$

Step-by-step explanation:

Let the distance between village and school be x km :

We know :

Time = Distance / Speed :

Given that total time is 9 hours.

Now let's solve the equation : A.T.Q.

$\displaystyle{\frac{x}{5}+ \frac{x}{4} =9}\\\\\\\displaystyle{x\left(\frac{1}{5}+\frac{1}{4}\right)=9}\\\\\\\displaystyle{x\left(\frac{9}{20}\right)=9}\\\\\\\displaystyle{x=\frac{9\times20}{9}}\\\\\\\displaystyle{x=20 \ \text{km}}$

Hence we get answer.