Question

A triangular park ABC has sides 120m, 80m and 50m (see Fig. 12.7). A
gardener Dhania has to put a fence all around it and also plant grass inside. How
much area does she need to plant? Find the cost of fencing it with barbed wire at the
rate of Rs 20 per metre leaving a space 3m wide for a gate on one side​

Answer 1

Answer:

here, a=120m,

b=80m,

c=50m

and, s= a+b+c/2

= 250/2

=125

Area she need to plant grass =

s(s−a)(s−b)(s−c)

=

125(125−120)(125−80)(125−50)

=375

15 m^2

cost of fencing =[(a+b+c)−3].20

=[250−3].20

=Rs4940