Question

The edges of a triangular board are 6 cm, 8 cm and 10 cm. The cost of painting it at the rate of Rs. 9 per sq. cm is:​

Answer 1

Answer: Rs 2.16

Step by step expantion :

= 2a+b+c

= 26+8+10

=12By Heron's formula,Area of the triangle = s(s−a)(s−b)(s−c)

= 12(12−6)(12−8)(12−10)

= 12(6)(4)(2)

=24cm

Cost of painting =9×24 paise =216 paise = Rs. 2.16