NIELIT 2023 Feb Scientist D | Section D | Question: 103

Question

Subhash can copy $50$ pages in $10 \mathrm{hrs,}$, Subhash and Prakash together can copy $300$ pages in $40 \mathrm{hrs}$. In how much time can Prakash copy $30$ pages.

• A. $13 \mathrm{hrs}$
• B. $12 \mathrm{hrs}$
• C. $11 \mathrm{hrs}$
• D. $9 \mathrm{hrs}$

   

Answer 1

Subhash $1$ hr work=$50/10=5$ pages

the number of pages copied by Subhash +prakash in $1$ hr=$300/40=7.5$ pages

So Prakash can copy pages in $1$ hr=$7.5-5=2.5$ pages

$\because 2.5$ pages copied $\rightarrow 1$ hr

$\therefore 30$ pages can copied $\rightarrow\frac{30}{2.5}=12$ hr

Option $(B)$ is correct.