Question

What length of canvas cloth,which is 3m wide,is used to make a conical tent 10m in diameter and 4.2m in slant height? find the cost of the canvas cloth at the rate of rs 2.50 per m

Answer 1

Slant height = 4.2 m
Radius = Diameter÷2 = 10÷2 = 5 m
so curved surface area = π r l
22/7 × 5 × 4.2
curved surface area  = 66 m²
It is given that the width of the canvas cloth is 3 m.
So, length of the canvas cloth used = Curved surface area/width
= 66/3 = 22 m
Total cost of canvas cloth used at the rate of Rs. 2.50 per m.
= length of the canvas cloth used × rate per metre
= 22 × 2.50
= Rs. 55

Hope This Helps.

Answer 2

Given, width = 3m
 
            height = 4.2m

            radius = d/2 = 10/2 = 5

          curved surface area = pi * r * l

                                            = 3.14 * 5 * 4.2

                                            = 65.94

                                            = ~66m^2

Length of the canvas cloth = curved surface area/width

                                              = 66/3

                                              = 22m.

Total cost of canvas at the rate of Rs 2.50 per meter = 22 * 2.50

                                                                                        = 55.



Hope this helps!