Q27 of 69 Page 240

If the sides of a triangular field measures 52m, 37 m and 20 m, then the cost of leveling at Rs 5 per m2 is Rs 1530.

Let the sides of the triangular field be:

a = 52 m, b = 37 m and c = 20 m


∴ s =


=


=


= 54 m


Now, by using Heron’s formula we get:


Area of triangle =


=


=


=


= 17 × 2 × 3 × 3


= 306 m2


It is given that,


Cost of leveling 1 m2 area = Rs 5


∴ Cost of leveling 306 m2 area = 5 × 306


= Rs 1530


Hence, the given statement is true


More from this chapter

All 69 →
25

If the base of an isosceles triangle is 6cm and its perimeter is 16cm, then its area is 12cm2.

 26

If each side of an equilateral triangle is 8cm long, then its area is cm2.

 28

Match the following columns.























Column I



Column II



(a) The lengths of three sides of a triangle are 26 cm, 28 cm and 30cm. The height corresponding to base 28cm is……cm



(p) 6



(b) The area of an equilateral triangle is cm2. The perimeter of the triangle is…..cm



(q) 4



(c) If the height of an equilateral triangle is cm, then each side of the triangle measures …. Cm



(r) 24



(d) Let the base of an isosceles triangle be 6 cm and each of the equal side be 5cm. Then, its height is ….cm



(s) 12



The correct answer is :


(a)-…….. (b)-……..


(c)-……… (d)-………

 29

A park in the shape of a quadrilateral ABCD has AB = 9m, BC = 12m, CD = 5 cm, AD = 8 m and c= 90°. Find the area of the park. [Given: = 5.9]