Question

the diameter of earth is 4 times that of moon. What is the ratio of their surface areas?

Answer 1

Answer:

16:1 is the ratio of surface areas of earth and moon respectively if taken as a sphere

Answer 2

Answer:

The ratio is 16:1

Step-by-step explanation:

Let diameter of Earth =D units

∴ Radius of Earth =2R units

Let diameter of moon =d units

Radius of mood =2r units

Given, D=4d

2R=4×2r

R=4r

$\frac{surface \: area\: of \: earth}{surface \: area \: of \: moon} = \frac{4\pi(4r {}^{2}) }{4\pi \: r {}^{2} } = \frac{64\pi \: r {}^{2} }{4\pi \: r {}^{2} } = \frac{16}{1}$

∴ The ratio is of surface area of Earth to Surface area of moon is 16:1