Question

a gardener wants to fence a circular garden of diameter 21m find the length of the wire he needs to purchase and cost of Rs 4 per metre

Answer 1

diameter of circular garden is 21m
NOW,
circumference =2πr
=22/7*21
=22*3
=66m
cost of wire is 4 per meter
Total cost of wire =66*4
=Rs264 ans.

Answer 2

Answer:

Solution- diameter of the circular garden= 21 m

radius= 21/2 m

circumference= 2πr

∴ circumference of the circular garden= 2*22/7*21/2 m

                                                                =22*3 m=66 m

since, the rope makes 2 round of fence.

∴length of the rope= 2* (circumference of the garden)

                               = 2*66 m= 132 m

    thus , the length of the required rope =132 m

now,      cost of the rope= rs 4 *132= rs 158