Question

15 practice problems
2 a cereal box is 8 inches by 2 inches by 12 inches. what is its surface area? show your reasoning. if you get stuck, consider drawing a sketch of the box or its net and labeling the edges with their measurements.

Explanation:

Step1: Recall surface - area formula for a rectangular prism

The surface - area formula of a rectangular prism with length $l$, width $w$, and height $h$ is $SA = 2(lw+lh + wh)$.

Step2: Identify the dimensions

Given $l = 8$ inches, $w = 2$ inches, and $h = 12$ inches.

Step3: Calculate $lw$, $lh$, and $wh$

$lw=8\times2 = 16$ square inches, $lh=8\times12 = 96$ square inches, $wh=2\times12 = 24$ square inches.

Step4: Calculate the surface area

$SA = 2(16 + 96+24)$
$SA = 2\times136$
$SA = 272$ square inches.

Answer:

272 square inches