In a recent survey,$40 \%$ of houses contained two or more people. Of those houses containing only one person,$25 \%$ had only a male. What is the percentage of all houses that contain exactly one female and no males (in $\%$)?

If $x$ is $90 \%$ of $y,$ then what per cent of $x$ is $y$?

In an examination,it is required to multiply a number by $7$,but by mistake,a student divides it by $7$. What is the error percentage?

The production of a company has ups and downs every year. The production increases for two consecutive years consistently by $15 \%$ and in the third year it decreases by $10 \%$. Again in the next two years it increases by $15 \%$ each year and decreases by $10 \%$ in the third year. If we start counting from the year $1998$,approximately what will be the effect on the production of the company in $2002$?

The price of a car is ₹ $325000$. It was insured to $85 \%$ of its price. The car was damaged completely in an accident and the insurance company paid $90 \%$ of the insurance. What was the difference between the price of the car and the amount received?

$0.15 \%$ of $33 \frac{1}{3} \%$ of $Rs. 10,000$ is?