Question

Ten years ago a forest was spread up to a distance of 33 km. Due to forest fires and industrial set up now it is spread upto a distance of $16\frac{1}{5}$ km. What fraction of forest has been destroyed in the last 10 years?

Answer 1

Fraction of forest destroyed in last 10 years
= Forest coverage 10 years ago - Forest coverage today
= 33 km - $16\frac{1}{5}$ km

Let's convert mixed fraction to improper fraction first.
$16\frac{1}{5}=\frac{16\times 5+1}{5}=\frac{81}{5}$

So, forest destroyed = $33-\frac{81}{5}$
= $\frac{33\times 5-81}{5}$
=$\frac{165-81}{5}$
=$\frac{84}{5}$
=$16\frac{4}{5}$ km