Question

2. The radius and height of a right circular cone are in
the ratio 4:3. If the area of the base of the cone is 154
cm2 , find its curved surface area.​

Answer 1

Answer:

The Curved Surface Area of the right circular cone is 115.2 sq.cm

Step-by-step explanation:

Let the radius be r and the height be h

In a right circular cone,

radius, r = 4a

height, h = 3a

Area of the base of cone = Area of circle = 154 sq.cm

$\pi {r}^{2} = 154$

$\frac{22}{7} {(4a)}^{2} = 154$

${a}^{2} = \frac{49}{16}$

$a = \frac{7}{4}$

So, the radius of the cone is 7cm and height of the cone is 21/4 cm

Curved Surface Area of the cone = $\pi \times r \times h \: sq.units$

$= \frac{22}{7} \times 7 \times \frac{21}{4}$

= 115.2 sq.cm