Question

luas permukaan balok

Answer 1

No. 1

A. volume balok :

• v = p × l × t
• v = 10 cm × 7 cm × 5 cm
• v = 350 cm³

B. luas perm balok :

• L = 2 × (p × l) + 2 × (p × t) + 2 × (l × t)
• L = 2 × (10 cm × 7 cm) + 2 × (10 cm × 5 cm) + 2 × (7 cm × 5 cm)
• L = 2 × (70 cm²) + 2 × (50 cm²) + 2 × (35 cm²)
• L = 140 cm² + 100 cm² + 70 cm²
• L = 310 cm²

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No. 2

Luas perm balok :

• L = 2 × (p × l) + 2 × (p × t) + 2 × (l × t)
• L = 2 × (16 cm × 8 cm) + 2 × (16 cm × 12 cm) + 2 × (8 cm × 12 cm)
• L = 2 × (128 cm²) + 2 × (192 cm²) + 2 × (96 cm²)
• L = 256 cm² + 384 cm² + 192 cm²
• L = 832 cm²

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No. 3

A. tinggi balok :

• t = v ÷ (p × l)
• t = 1.200 cm³ ÷ (15 cm × 10 cm)
• t = 1.200 cm³ ÷ 150 cm
• t = 8 cm

B. luas perm balok :

• L = 2 × (p × l) + 2 × (p × t) + 2 × (l × t)
• L = 2 × (15 cm × 10 cm) + 2 × (15 cm × 8 cm) + 2 × (10 cm × 8 cm)
• L = 2 × (150 cm²) + 2 × (120 cm²) + 2 × (80 cm²)
• L = 300 cm² + 240 cm² + 160 cm²
• L = 700 cm²