GMAT OFFICIAL GUIDE PS

Solution:

We are given a painting that has 4 different colored rectangles, each with a length of l and a width of w. We are also given that the entire painting has an area of 4,800 square inches. Let’s begin by sketching the given diagram. We can also add in the appropriate dimensions to each side.

The figure shown above represents a modern painting...

From the diagram we can create an equation:

l = w + w + w

l= 3w

We also know that the area is 4,800 square inches. Using the dimensions from our diagram and the formula for the area of a rectangle, we can say:

l(w + l) = 4,800

Since l = 3w, we can substitute 3w for l in the area equation l(w + l) = 4,800. Thus, we have:

3w(w + 3w) = 4,800

3w(4w) = 4,800

12w^2 = 4,800

w^2 = 400

w = ±20

Because we are dealing with a measurement, we disregard w = -20 as a solution. Thus, the width of each rectangle is 20 inches.

Answer: B

About The Author

Scott Woodbury-Stewart is the founder & CEO of Target Test Prep. A passionate teacher who is deeply invested in the success of his students, Scott began his career teaching physics, chemistry, math, and biology. Since then, he has spent more than a decade helping students gain entry into the world’s top business schools, logging 10,000+ hours of GMAT, EA, GRE and SAT instruction. Scott also served as lead content developer and curriculum architect for the revolutionary courses Target Test Prep GMAT, Target Test Prep EA, Target Test Prep GRE and Target Test Prep SAT Quant.