Question

Solve linear equation:
$\frac{n}{2}-\frac{3n}{4}+\frac{5n}{6}=21$

Answer 1

Given equation is $\frac{n}{2}-\frac{3n}{4}+\frac{5n}{6}=21$
LCM of $2,4$ and $6$ is $12$
$\Rightarrow \frac{6n-9n+10n}{12}=21$
$\Rightarrow \frac{7n}{12}=21$
Multiply both sides by $12$
$\frac{7n}{12}\times 12=21\times 12$
$7n=252$
$n=\frac{252}{7}$
$\therefore n=36$