# math

posted by
**claire** on
.

The brightness of a light bulb varies inversely as the square of the distance from the source. If a light bulb has a brightness of 300 lumens at 2 ft, what will its brightness be at 10 ft?

posted by
**claire** on
.

The brightness of a light bulb varies inversely as the square of the distance from the source. If a light bulb has a brightness of 300 lumens at 2 ft, what will its brightness be at 10 ft?