SAT Math Multiple Choice Practice Question 468: Answer and Explanation
In the figure above, the perimeter of square FCDE is how much smaller than the perimeter of rectangle ABDE ?
Correct Answer: C
C Remember that the perimeter is the sum of all the sides. FCDE is a square, so all the sides are equal. Because = 3, each side of the square is 3, so you know that , , and are all 3. ABDE is a rectangle, which means that the opposite sides are equal. = 2, so = 2 also. Along the same lines equals 3, so that means the opposite side, , also equals 3. Add up all the sides of ABDE to find the perimeter: 2 + 2 + 3 + 3 + 3 + 3 = 16. To find out how much smaller the perimeter of FCDE is, just subtract: 16 – 12 = 4.