Question

Directions for questions 35 to 40: Study the following details about a family's monthly income and expenditure and answer the question that follows.

Income	Amount / Rate
Basic salary	Rs. 5,000
Petrol allowance	20% of basic salary
PF deduction	10% of basic salary

Expenditure	Share of net income
Food	28%
House rent	22%
Entertainment	12%
Children's Education	25%
Other expenses	13%

What is the house rent?

• A. Rs. 1188
• B. Rs. 1210
• C. Rs. 1320
• D. Rs. 1420

Hint:

Work out the family's net income after the PF deduction, then take 22 percent of it.

Answer 1

The Correct Option is B

Step 1: Find the net income with a shortcut.
Both the petrol allowance and the PF deduction are given as a percent of the basic salary.
Adding a 20 percent allowance and then taking away a 10 percent deduction, both measured on the basic salary, works out the same as scaling the basic salary once by $(100 + 20 - 10)$ percent, that is, by 110 percent.
\[ \text{Net income} = 5000 \times 1.10 = 5500 \]

Step 2: Find the value of 1 percent of the net income.
\[ 1\% \text{ of } 5500 = 55 \]
This single number lets us read off any of the expenditure heads quickly, since each is just a multiple of 55.

Step 3: Scale up to 22 percent for the house rent.
\[ 22 \times 55 = 1210 \]

Final Answer:
The family pays Rs. 1,210 as house rent. \[ \boxed{Rs.\ 1210} \]