Question

Express $\frac{5}{7}$ as a rational number with denominator:
(i) −14
(ii) 70
(iii) −28
(iv) −84

Answer 1

$\frac{5}{7}$ as a rational number with denominator:
(i) −14 is:

$\frac{5\times -2}{7\times -2}=\frac{-10}{-14}(\mathrm{Multiplyin}\text{g}\mathrm{numerator}\mathrm{and}\mathrm{denominator}\text{by}-2)$
(ii) 70 is:

$\frac{5\times 10}{7\times 10}=\frac{50}{70}(\mathrm{Multiplying}\mathrm{numerator}\mathrm{and}\mathrm{denominator}\text{by}10)$

(iii) −28 is:

$\frac{5\times -4}{7\times -4}=\frac{-20}{-28}(\mathrm{Multiplying}\mathrm{numerator}\mathrm{and}\mathrm{denominator}\text{by}-4)$

(iv) −84 is:

$\frac{5\times -12}{7\times -12}=\frac{-60}{-84}(\mathrm{Multiplying}\mathrm{numerator}\mathrm{and}\mathrm{denominator}\text{by}-12)$