Question

a classroom board is 18 inches wide and 16 inches tall. kenji is putting ribbon along the outside edge of the board. how many inches of ribbon will he need?

Explanation:

Step1: Identify the shape and formula

The board is a rectangle, and we need to find the perimeter. The formula for the perimeter \( P \) of a rectangle is \( P = 2\times (length + width) \). Here, length \( l = 18 \) inches and width \( w = 16 \) inches.

Step2: Substitute values into the formula

Substitute \( l = 18 \) and \( w = 16 \) into the formula: \( P = 2\times(18 + 16) \).
First, calculate the sum inside the parentheses: \( 18 + 16 = 34 \).
Then, multiply by 2: \( 2\times34 = 68 \).

Answer:

68