A woman buys a house for Rs 40 Lac and rents it. She puts 15% of each month's rent aside for repairs and pays Rs 3000 as annual tax. If she realizes 20% on her investment thereafter then find the monthly rent of her house?
Rs 70135.5
Rs 78725.5
Rs 79566.5
Rs 80221.5
Answer: (b) Rs 78725.5Solution: Let the annual rent of the house is Rs \(x\) then.\(x - (15 \ \% \ of \ x + 3000)\) = \(20 \ \% \ of \ 4,000,000\)\(x - \frac{15x}{100} - 3000\) = 800,000\(x - \frac{15x}{100} = 803,000\)\(\frac{85x}{100} = 803,000\)\(x = 944,705.89\)\(\approx 944,706\)Hence monthly rent of the house.\(= \frac{944,706}{12}\)\(= Rs \ 78,725.5\)
If \(z = \frac{x^2}{y}\) and \(x\), \(y\) are both increased in value by 10% then find the percentage change in the value of \(z\)?
10 %
11 %
12 %
13 %
Answer: (a) 10 %Solution: After increasing the value of \(x\) and \(y\) by 10%. $$ x = \frac{110x}{100} $$ $$ x = \frac{11x}{10} $$ $$ y = \frac{110y}{100} $$ $$ y = \frac{11y}{10} $$ $$ z = \frac{x^2}{y} $$ $$ z = \frac{\left[\frac{11x}{10}\right]^2}{\frac{11y}{10}} $$ $$ z = \frac{11}{10} \times \frac{x^2}{y} $$ $$ z = \frac{11z}{10} $$ The increase in the value of z. $$ = \frac{11z}{10} - z $$ $$ = \frac{z}{10} $$ Hence the percentage increase in the value of z. $$ = \frac{z}{10} \times \frac{100}{z} $$ $$ = 10 \ \% $$
If the wage of an employee reduced by 25% and again increased by 50% then the final loss or profit of that employee in percentage?
12.5 % Profit
12.5 % Loss
10.5 % Profit
10.5 % Loss
Answer: (a) 12.5 % ProfitSolution: Let the initial wage of the employee was $100 then.Wage after reducing 25% = 75 % of 100. $$ = \frac{75}{100} \times 100 $$ $$ = $75 $$ Final wage after increasing 50% = 150 % of 75. $$ = \frac{150}{100} \times 75 $$ $$ = $112.5 $$ Hence the employee is in profit of 12.5 %.
If the price of petrol increased by 20% then how much percent, a car owner should use less petrol so as not to increase his expenditure on petrol?
The population of a town is 40,000. If it increases at the rate of 10% per annum then what will be the population of the town after 2 years?
48,250
48,400
48,500
48,650
Answer: (b) 48,400Solution: Given \(k = 40,000\), \(n = 10\), and \(x = 2\) then the population of the town after 2 years. $$ = k \times \left[1 + \frac{n}{100}\right]^x $$ $$ = 40,000 \times \left[1 + \frac{10}{100}\right]^2 $$ $$ = 40,000 \times \frac{11}{10} \times \frac{11}{10} $$ $$ = 48,400 $$ Hence the population of the town after 2 years will be 48,400.