Question

In each of the following, check whether or not the given ratios form a proportion:​
(i)$25:40$ $\text{and}$ $20:32$

Answer 1

Given expression can be written as,
$25:40=\frac{25}{40}=\frac{5\times 5}{5\times 8}=\frac{5}{8}$

$\text{and}$

$20:32=\frac{20}{32}=\frac{4\times 5}{4\times 8}=\frac{5}{8}$

$\therefore$ $25:40=20:32$

Hence they form a proportion.