The surface area of a right circular cone is 20 cm. The radius of the base and the slant height are each multiplied by 5, enlarging the cone. What is the surface area of the new cone?

Answer

The surface area of the new cone is 240 inches^2

Step-by-step explanation:

If the two cones are similar, then

R1 / R2 = L1 / L2 =Constant ratio

S. A1 / S. A2 = ( R1/ R2)^2

V1 / V2 = ( R1 / R2)^3

The surface area of a right circular cone is 15 inches^2

The cone is enlarged by multiplying both the radius of the base and the slant height by 4

The two cone are similar

R1 / R2 =1/4

The surface area of a right circular cone is 15 inches^2

S.A1 / S. A2 = ( R1/R2) ^2

By using cross multiplication

15 × 16 = S. A2× 1

240 = S. A2

The surface area of the enlarged cone = 240 inches^2

13cm

step-by-step explanation:

(apex)