Final answer:
To find the width of a rectangular poster with a perimeter of 124 inches and a length that is 10 inches longer than the width, set up the perimeter equation, solve for the width, and find that the width is 26 inches.
Step-by-step explanation:
The student asks to find the width of a rectangular poster where the length is 10 inches longer than the width, and the perimeter is 124 inches.
Firstly, let's denote the width of the poster as w inches. Therefore, the length is w + 10 inches. The formula for the perimeter of a rectangle is P = 2l + 2w, where P is the perimeter, l is the length, and w is the width.
We can set up the equation for the given perimeter:
2(w + 10) + 2w = 124
Simplifying the equation:
2w + 20 + 2w = 124
4w + 20 = 124
4w = 104
w = 26
The width of the poster is 26 inches.