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प्रश्न
Three cubes each of side 10 cm are joined end to end. Find the surface area of the resultant figure.
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उत्तर
If three cubes each of side 10 cm are joined, then a cuboid will be formed of dimensions 30 cm × 10 cm × 10 cm.
∴ Surface area of the cuboid = `2[lb + bh + hl]`
= 2[30 × 10 + 10 × 10 + 30 × 10]
= 2[300 + 100 + 300]
= 2[700]
= 1400 cm2
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