Question

$\text{The product of two rational numbers is -5.}\text{If one these numbers is}\frac{-7}{15},\text{find the other.}$

Answer 1

$\text{Let the required rational number be=x}\text{Other number}=\frac{-7}{15}\text{Product of rational numbers=-5}\Rightarrow \frac{-7}{15}\times x=-5\Rightarrow -7x=-5\times 15\Rightarrow x=\frac{-75}{-7}=\frac{75}{5}\therefore \text{The required reational number}=\frac{75}{7}$