Question

By what number should $9\frac{4}{5}$ be multiplied to get 42?

Answer 1

Product of the two numbers = 42
One of the numbers = $9\frac{4}{5}$ = $\frac{49}{5}$
∴ The other number = $\left(42÷\frac{49}{5}\right)$
=$\left(42\times \frac{5}{49}\right)$ [∵ Reciprocal of $\frac{49}{5}$ = $\frac{5}{49}$]
=$\left(\frac{6\times 5}{7}\right)=\frac{30}{7}=4\frac{2}{7}$

Hence, the required number is $4\frac{2}{7}$.