UP Police Constable Exam Model Paper 5

Given,
Initial Expenditure $=75\%$ Initial Savings $=25\%$
Increase in income $=20\%$
Increase in expenditure $=20\%$
Concept:
To solve this type of question, consider the initial income to be 100 . Then, calculate the rest of the data using simple $\%$ rulesSolution:
Let the income be 100 .
Expenditure $=75\%$ of $100=75$
Savings $=25\%$ of $100=25$
$\%$ increase income $=20\%$
New income $=120$
$\%$ increase in expenditure $=20\%$ of $75=15$

New expenditure $=75+15=90$
New savings $=$ New income $-$ new expenditure $=120-90=30$
$\%$ increase in savings $=\left[\left(30-25\right)/25\right]\times 100$
$=20\%$
∴ Increase in savings is $20\%$