There is 80% increase in amount in 5 years at simple interest. What will be the compound interest of Rs. 20,000 after 3 years at the same rate?

The covered surface area of  a cone of radius 8 cm and height 6 cm is double the covered surface area of a cylinder of radius 4 cm. Find the height of the cylinder?

Mohit borrowed Rs. 22000 at 5% simple interest repayable in 5 equal installments. What will be the annual installment payable by him?

Sides of a triangle are 13 cm, 84 cm and 85 cm. Find its area(in square cm)?

After an increase in tea price by 40% a family reduce its consumption of tea to the extent that there should be an increase on tea expense only by 10%. If the earlier consumption of tea was 28 kg, then what will be their new consumption?

Rectangle ABCD is formed in a circle with centre D. IF AE=6 cm and AD=9 cm, then find the perimeter of the rectangle.

In the given figure, ABC is an equilateral triangle. Two circles of radius 4 cm and 12 cm are inscribed in the triangle. What is the side (in cm) of an equilateral triangle?

In the given figure, PQRS is a square of side 20 cm and SR is extended to point T. If the length of QT is 25 cm, then what is the distance (in cm) between the centres O₁ and O₂ of the two circles?