Question

Ravi and Kumar are working on an assignment. Ravi takes $6$ hours to type $32$ pages on a computer, while Kumar takes $5$ hours to type $40$ pages. How much time will they take, working together on two different computers to type an assignment of $110$ pages?

• A. $20$ hours
• B. $5$ hours $40$ minutes
• C. $8$ hours $15$ minutes
• D. $23$ hours

Answer 1

Answer: (C)

$8$ hours $15$ minutes

Number of pages typed by Ravi in 1 hour$=\frac{32}{6}=\frac{16}{3}$
Number of pages typed by Kumar in 1 hour$=\frac{40}{5}=8$
Number of pages typed by both in 1 hour$=(\frac{16}{3}+8)=\frac{40}{3}.$
$\therefore$ Time taken by both to type 110 pages$=(110\times \frac{3}{40})$hours.
$=8\frac{1}{4}$ hours (or) 8 hours 15 minutes..