For the following questions answer them individually
The radius of a wheel is 21 cm. What is the distance (in cm) travelled by the wheel in 20 revolutions?
Dinesh makes four trips of equal distances. His speed on first trip was 140 km/hr and in each subsequent trip his speed was half of the previous trip. What is the average speed of Dinesh in these four trips?
Krishna travels from point A to point B in 6 hours and returns back to point A from point B in 5 hours. Point A and point B are 220 miles apart along a straight highway. What is the average speed of Krishna for the whole journey?
What is the compound interest on Rs. 16400 for 1 year at 9% per annum when compounded half-yearly?
Vijay sells bananas at the rate of Rs. 13 per dozen and earns a profit of 30 percent. The cost price of the bananas increases by 10 percent. If they selling price remains the same, then what is his new profit percent?
Height of a cone is 12 cm and radius of its base is 14 cm. What is the volume of the cone?