DELHI POLICE MATHS QUIZ

The average age of a husband and wife. Who were married 4 years ago was 28 years at the time of their marriage. The average age of the family consisting of husband, wife and a child born during the interval is 23 years today. The age of the child is:

A and B can do a piece of work in 25 days. B alone can do $66\frac{ 2}{3}$% of the same work in 30 days. In how many days can A alone do 4/15 part of the same work?

The average speed of a car which covers half the distance with a speed of $20 \mathrm{~km} / \mathrm{h}$ and the other half with a speed of $30 \mathrm{~km} / \mathrm{h}$, will be:

A solid metallic cube with side $9 \mathrm{~cm}$ and a solid metallic cuboid having dimensions $5 \mathrm{~cm}, 13 \mathrm{~cm}, 31 \mathrm{~cm}$ are melted and recast into a single cube. What is the total surface area (in $\mathrm{cm}^2$ ) of the new cube?

Ritu's expenditure and saving are in the ratio $5: 2 .$ Her income increases by $12 \%$. Her expenditure also increases by $14 \%$. By how many $\%$ does her saving increase?

HDFC bank lent Rs. X to a farmer at $12.5 \%$ p.a. for 1 year 73 days. How much compound interest the former had to pay it the simple interest for the first year is Rs.4,000? The values of compound interest and sum lent are given in the options below; choose the correct option.

Find the greatest value of $\mathrm{k}$ for which the 6 -digit number $24312 \mathrm{k}$ is divisible by 6 .

The value of $500 \div \frac{3}{8}$ of $\frac{2}{3} \div\left[\frac{5}{3}\right.$ of $\left.300+7 \frac{1}{2} \div 5 \frac{1}{2} \times 1100\right]$ is:

In a city, 80% registered voters cast their votes in the election. Only two candidates contested the election. Raju won the election by 800 votes. Had Raju received 25% less votes, the result would have been tie. How many registered voters are there in the city?

A trader purchased 132 dozens of mangoes at Rs. 475 per dozen and could sell only 125 dozens at Rs. 530 per dozen. What is the value of stock of mangoes in hand (in rupees)?