The dimensions of a page are 12 in. by 10 in. and it is supposed to contain 80in2 of the printed region. What should the margin be if all the margins are the same?
80 in^2 = 10 in by 8 in.
That leaves a margin of 1 inch on all four sides of the printed area.
(12-2x)(10-2x) = 80
Solve that for x, or just note that
80 = 10x8, so both dimensions are reduced by 2", making a 1" margin all around.
To determine the margin size, we need to find the area of the printed region and then calculate the margin.
1. Calculate the area of the entire page:
Area = length × width
Area = 12 in. × 10 in.
Area = 120 in²
2. Subtract the desired printed region area from the total page area to get the remaining area for the margins:
Marginal area = Total area - Printed area
Marginal area = 120 in² - 80 in²
Marginal area = 40 in²
3. Since all margins are the same size, divide the marginal area by the number of margins (4) to find the size of each margin:
Marginal size = Marginal area / Number of margins
Marginal size = 40 in² / 4
Marginal size = 10 in²
Therefore, the margin size should be 10 in.