Question

Velan and karan together can build a bridge in 5hrs.karan works twice as long as velan does if he has to do the job alone.how long will it take velan to complete the job alone

Answer 1

Answer:

Velan completes the work in 7.5 hours

Step-by-step explanation:

Let Velan builds a bridge in x hours

Then Karan will build the bridge in 2x hours

In 1 hour, the work done by Velan = 1/x

In 1 hour, the work done by Karan = 1/2x

Since Karan and Velan can build a bridge in 5 hours

Therefore

$5(\frac{1}{x}+\frac{1}{2x})=1$

$\implies \frac{1}{x}+\frac{1}{2x}=\frac{1}{5}$

$\implies \frac{3}{2x}=\frac{1}{5}$

$\implies x=\frac{15}{2}$

$\implies x=7.5$ hours

Hope the answer is helpful to you.