A10-by-12-inch page has margins of 1.5 inches on all sides. what fraction of the area of the page is taken up by the margins? express your answer as a common fraction.

To determine the fraction of the area that is taken up by the margins, we need to calculate for the area of the margins and divide it with the total area of the page. We do as follows:

Area of margins = 2(L1W1) + 2(L2W2)

where L1, W1 represents the length and the width of the margin that is longer and L2 and W2 represents the length and width of the margin that is shorter. 

L1 = 12
W1 = 1.5
L2 = 7
W2 = 1.5

Area of the margins = = 2((12)(1.5)) + 2((7)(1.5)) = 57 square inches

Total area of the page = 10 in x 12 in = 120 square inches

fraction taken by the margins = 57 square inches / 120 square inches = 0.475