Gross income = Rs. 20000 Income exempted from income tax = 10% of gross income ∴ Income on which income tax is chargeable = (100 – 10%) = 90% of gross income =20000×
90
100
= Rs. 18000 ∴ Total income tax paid on = Rs. 20000 – Rs. 19100 = Rs. 900 ∴ Rate per cent of income tax =