Which of these objects has the smallest surface area to volume ratio?
Answer and explanation
Correct answer: B. A cube of side 4 cm
- Step 1: Cube of 4 cm: SA 96, V 64, ratio 1.5:1. Step 2. Cube of 2 cm: SA 24, V 8, ratio 3:1. Step 3. Cuboid 2x2x4: SA 40, V 16, ratio 2.5:1; sheet: SA 144, V 32, ratio 4.5:1. Answer: A cube of side 4 cm. Why not the others: the other three shapes all have ratios of 2.5:1 or greater, so they are less compact.
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