Difficulty: Easy
Correct Answer: 0.08
Explanation:
Introduction / Context:
The mean proportional (geometric mean) m between two positive numbers a and b satisfies a : m = m : b, or m^2 = a * b. Hence m = sqrt(a * b). Compute accurately with decimals.
Given Data / Assumptions:
Concept / Approach:
Multiply the two decimals and take the square root. Keep precision to avoid rounding errors that might push you toward a nearby option.
Step-by-Step Solution:
Product = 0.32 * 0.02 = 0.0064m = sqrt(0.0064) = 0.08
Verification / Alternative check:
Check proportion: 0.32 : 0.08 = 4 : 1 and 0.08 : 0.02 = 4 : 1; proportions match, confirming m.
Why Other Options Are Wrong:
0.34 and 0.30 are far too large; 0.16 would be m^2, not m; 0.06 does not satisfy the proportion check.
Common Pitfalls:
Confusing arithmetic mean with geometric mean; forgetting to take the square root after multiplying.
Final Answer:
0.08
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