Area

11 The area of a triangle is 216 cm° and it's sides are in the ratio 3 : 4 : 5. The perimeter of the triangle is

12 The area of a rectangular field is 400 sq m. If the breadth of the field is 16 m, find the length of the field:

13 The base of a parallelogram is twice it's height. If the area of the parallelogram is 144 sq cm, find it's height:

14 A hall, whose length is 16 m and breadth twice it's height takes 168 m of paper 2 m wide for it's four walls. Find the area of the floor:

15 The perimeter of an equilateral triangle is 90 cm. Find it's area:

16 The areas of a square and rectangle are equal. The length of the rectangle is greater than the length of any side of the square by 5 cm and the breadth is less by 3 cm. Find the perimeter of the rectangle:

17 The length of one pair of opposite sides of a square is increased by 5 cm on each side, the ratio of the length and the breadth of the newly formed rectangle becomes 3 : 2. What is the area of the original square?

18 If the sides of a rectangle are increased by 5%, find the percentage increase in it's diagonals:

19 The base of a parallelogram is twice it's height. If the area of the parallelogram is 144 sq cm, find it's height:

20 The area of a rectangle is 1.8 times the area of a square. The length of the rectangle is 5 times the breadth. The side of the square is 20 cm. What is the perimeter of the rectangle?