Question

By what numbers should $\frac{-15}{28}$ be multiplied, so that the product may be $\frac{-5}{7}$?

Answer 1

Given:
Product of two numbers $=\frac{-15}{28}$
one of the numbers $=\frac{-5}{7}$
Then the other number $=$ product of the numbers $÷$ given number
$=\frac{-15}{28}÷\left(\frac{-5}{7}\right)$ [$\because \frac{a}{b}÷\frac{c}{d}=\frac{a}{b}\times \frac{d}{c}$]

$=\frac{-3}{4}\times \frac{1}{-1}$
$=\frac{3}{4}$

Therefore, the other number is $\frac{3}{4}$.