?

SAT® Math

Free Version

Upgrade subject to access all content

Moderate

Inverse Square Law

SATMAT-5NRTHR

The amount of sunlight received by a planet per unit of surface area varies inversely with the square of its distance from the Sun. That is, if Planet B is twice as far away from the Sun as Planet A, Planet B will receive only one-fourth as much sunlight per unit of surface area as compared to Planet A.

The Earth is $93$ million miles from the Sun and Mars is $142$ million miles from the Sun.

Express the amount of sunlight received per unit of surface area on Mars as a percentage of the amount of sunlight the same unit of surface area would receive on Earth. Round to the nearest tenth of a percent.

A

$42.9\%$

B

$65.5\%$

C

$15.3\%$

D

$23.3\%$