How many pairs of twin primes are there between the integers 1 to 100? 

A student has to score 33% marks to pass. He gets 117 marks and fails by 81 marks. Find the student’s marks percentage?

HCF and LCM of two numbers are 7 and 140 respectively. If the numbers are between 20 and 45, the sum of the numbers is: 

The lengths of the parallel sides of a trapezium are 51 cm and 21 cm, and that of each of the other two sides is 39 cm. what is the area ( in cm²) of the trapezium?

Find the distance between the point (-6, 7) and the point (-1, -5).

Mr. Kiran sold a bus for Rs.18,700 at a loss of 15 %. At what price should the bus be sold to get a profit of 15 %?

A started the business with the investment of Rs. 36000. B and C joined him with some investments after 3 and 6 months. The profit is divided in the ratio of 2 ∶ 3 ∶ 5 at the end of the year. Find the difference between the investment made by B and C in the business.

Assume that
$$\sqrt{3} = 3.605 \ (approximately)  $$
$$\sqrt{130} = 11.40 \ (approximately)  $$
Find the value of
$$\sqrt{1.3} + \sqrt{1300}+\sqrt{0.013}  $$