Question

A 5-m-wide cloth is used to make a conical tent of base diameter 14 m
and height 24 m. Find the cost of cloth used at the rate of rupees 25 per metre.​

Answer 1

Answer:

here we have to find curved surface area of cone.

c.s.a of cone= πrl

r=14/2=7m

h=24m

l=√r^2 + h^2

l=√7^2+24^2

l=√49+576

l=√625

l=25m

C.S.A =π*7*25 m^2

C.S.A =22/7*7*25

C.S.A = 550 m^2

Cost of cloth = 550*25 = 13750 Rs

Answer 2

$\huge \pink {answer}$

Let the slant height of the cone be 'l' meters.

height

=

24

m and diameter

=

14

m or radius

=

7

m.

Then according to the question.

l²= h²+ r²

l 2

24

2

+

7 2

l 2

576+ 49

l 2

625

l=

625

m

l= 25

So, the slant height of the cone is 25 m.

Now,

Curved Surface Area of the cone

=

πrl

=

7

22

×

7×

25

CSA= 550m

2

Now, length of the cloth used = Area/ width of the cloth$$= \dfrac{550}{5}$$

Length of the cloth used

=

110m

Cost of cloth

=

Rs.25/meter

Total cost of clothe used

25×

110=

Rs.2750