Question

diameter of earth is 4 times dia.of moon find the ratio of the surface area of moon​

Answer 1

Answer: 1:16

Step-by-step explanation:

I assume you are asking for the ratio of surface area of moon to that of the Earth, if so  then :

surface area of sphere = 4πr²

let surface area of Earth = 4πR²

surface area of Moon = 4πr²

surface area of Moon ÷ surface area of Earth = r²/R² = (r/R)²

now given : diameter of Earth = 4 x diameter of Moon

⇒ 2R = 4 x 2r

⇒R = 4r or r/R = 1/4

∴ (r/R)² = 1/16

⇒ 1 : 16

Answer 2

Surface area of moon :-

=128614400km

Step-by-step explanation:

earth's radius is 6400km. So its diam. will be 12800km(d = 2r). Now diam of earth is 4 times the moon which means 4×d(of moon)

therefore diam of moon =12800÷4 = 3200

Now for surface area of moon.

let us consider moon to be of spherical shape.

So surface of sphere = 4(pi)r^2

=4×3.14×3200×3200

=128614400km.

(Hope it helps buddy) ✌