Question

A conical tent of radius 7 m and height 24 m is to be made. Find the cost of the 5 m wide cloth required at the rate of rs. 50 per metre.

Answer 1

Given radius And height= 7m and 24m
$slant \: height \: l = \sqrt{r} {}^{2} + \sqrt{h {}^{2} }$
$\sqrt{625 } = 25m$
C.S.A=πrl
$22 \div 7 \times 7 \times 25 = 550m {}^{2}$
Let xm of cloth is required C.S.A =Area of cloth
$5x = 550$
x= 110m
Cost of cloth
110×50=5500

Answer 2

Given:

A conical tent of,

radius (r) = 7 m

height (h) = 24 m

To Find:

Cost of the 5-meter wide cloth

Solution:

we know,

the slant height of cone (l)

l² = h² + r²

l² = 24² + 7²

l² = 576 + 49

l² = 625

l = 25

The curved surface area of the cone = πrl

⇒ 22/7 × 7 × 25

⇒ 550 m²

as given,

cost of  5 meter cloth = 50

so, cost of 550 = 50/5 × 550

                         = 550×10 rupees.

                         = 5500 rupees

Hence, the cost of the cloth is 5500 rupees.