Question
A right square pyramid has a base of side 10 cm and
slant height 13 cm. (a) Find its lateral surface area. (b) If its vertical height is 12 cm, find its volume.Solution
(a) Area of one triangular face = (1/2) × base × slant height = (1/2) × 10 × 13 = 65 cm² There are 4 faces: Lateral surface area = 4 × 65 = 260 cm² (b) Volume = (1/3) × (area of base) × height Base area = 10 × 10 = 100 cm² Volume = (1/3) × 100 × 12 = 400 cm³.
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15, 23, 35, 51, 71, 85 42, 32, 60, 48, 96, 84
Find the wrong number in the given number series.
20, 33, 50, 69, 93, 121
- Find the wrong number in the given number series.
420, 369, 318, 277, 238, 225 1648, 1690, 1741, 1807, 1938, 2140
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...Find the wrong number in the given number series.
1, 8, 27, 65, 125, 216A-5,  A,  35,  52, 78, 115
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