Question

find the value of b in the diagram below.
diagram: four rectangles each labeled b - 1, total length 16

Explanation:

Step1: Set up equation from diagram

$4(b-1) = 16$

Step2: Divide both sides by 4

$\frac{4(b-1)}{4} = \frac{16}{4}$
$b-1 = 4$

Step3: Solve for b

$b = 4 + 1$

Answer:

$5$