A prism has a base perimeter of 30 cm and height 7 cm. If its total surface area is 282 cm2, what is the area of both bases combined?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 72 cm2.
Perimeter base = 30 cm
Lateral surface area = Perimeter × Height = 30 × 7 = 210 cm2
Let the base area = B cm2
Total surface area = Lateral surface area + 2 × Base area
⇒ 282 = 210 + 2B
⇒ 2B = 72
⇒ B = 36 cm2
So both bases combined = 2 × 36 = 72 cm2