Question

a hollow cone 24 cm high with Base radius 7 cm is required to be made by a meta sheet.the area of metal sheet required including the Base is?

Answer 1

Radius=7cm
Height=24cm
we know that ,
slant height=√(h²+r²)

l=√(24²+7²)=√(576+49)=√625=25cm

l=25cm

Total surface are of cone=πr(l+r)

Total surface area=(22/7)×7(7+25)

Total surface area=(22/7)×7×32

Total surface area=704cm²

Hence metal sheet required to make cone including base=704cm²

Answer 2

Answer:

Option a - The area of metal sheet required including the base is 704 cm².

Step-by-step explanation:

Given : A hollow cone 24 cm high with Base radius 7 cm is required to be made by a meta sheet.

To find : The area of metal sheet required including the Base is?

Solution :

According to question,

Area required is the total surface area of the cone is $A=\pi r(l+r)$

We have given,

Radius r=7 cm

Height h=24 cm

Slant height l is given by,

$l=\sqrt{r^2+h^2}$

$l=\sqrt{7^2+24^2}$

$l=\sqrt{49+576}$

$l=\sqrt{625}$

$l=25$

Substitute the value in the formula,

$A=\pi r(l+r)$

$A=\frac{22}{7}\times 7(25+7)$

$A=22(32)$

$A=704$

Therefore, The area of metal sheet required including the base is 704 cm².

So, Option 'a' is correct.