math
posted by Bill .
A rectangular painting has an area of 720 square inches. It is to be reduced by 1/6 scale factor. What is area of the miniature copy.

Multiply the area of the rectangle by the square of the scale factor to get the area of reduced rectangle.
Reduced area = 720 * (1/6)^2
Reduced area = 720 * (1/36)
Reduced area = 720/6
Reduced area = ? sq in. 
720/36=20 sq. in. Let's say the original painting was 24x30" 24/6=4 30/6=5 4*5=20 sq. in., so the answer checks out!!