Mensurationhard · Past Paper
The base of a right pyramid is a square of side 10 cm. If its volume is 400 cubic cm, find its total surface area.
A360 sq. cm
B260 sq. cm
C400 sq. cm
D340 sq. cm
✓ Correct Answer: B — 260 sq. cm
Vol = 1/3 * 100 * h = 400 => h = 12. Slant height l = √(12² + 5²) = 13. LSA = 2 * 10 * 13 = 260. Base = 100. TSA = 360? Let's check: LSA = 260, Base = 100, TSA = 360. Correct.
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