Percentage Practice Test 2 with solutions

Let the number divided into two parts ${\mathit{x}}_1$ and ${\mathit{x}}_2$.
According to the statement,
(80% of ${\mathit{x}}_1$) = 3 + (60% of ${\mathit{x}}_2$)
$80\times \frac{{\mathit{x}}_1}{100}=3+60\times \frac{{\mathit{x}}_2}{100}$
$4{\mathit{x}}_1-3{\mathit{x}}_2=15$......(i)
6 + (90% of ${\mathit{x}}_1$) = (80% of ${\mathit{x}}_2$)
$6+\frac{90}{100}{\mathit{x}}_1=\frac{80}{100}{\mathit{x}}_2$
$9{\mathit{x}}_1=8{\mathit{x}}_2=-60$......(ii)
From solving equation (i) and (ii),
Multiplying equation (i) with 8 and equation (ii) by 3 and subtracting, we get,
${\mathit{x}}_1=60$
Substituting ${\mathit{x}}_1$ in equation (i) we get ${\mathit{x}}_2$
${\mathit{x}}_2=75$
So, the number is ${\mathit{x}}_1+{\mathit{x}}_1=60+75=135$.