Difficulty: Easy
Correct Answer: 9 : 4
Explanation:
Introduction / Context:For squares, the diagonal is proportional to the side and area scales with the square of any linear dimension. This item checks proportional reasoning by connecting a diagonal ratio directly to an area ratio without computing actual side lengths.
Given Data / Assumptions:
Concept / Approach:Because A ∝ d^2 for squares, the ratio of areas equals the square of the ratio of diagonals. No numeric side computation is necessary; simply square each term in the diagonal ratio and simplify the fraction to obtain the area ratio.
Step-by-Step Solution:
Given d1 : d2 = 3 : 2.Since A ∝ d^2, A1 : A2 = d1^2 : d2^2 = 3^2 : 2^2 = 9 : 4.The larger-to-smaller area ratio is 9 : 4.Verification / Alternative check:
Pick d2 = 2 ⇒ d1 = 3. Then A2 = 2^2/2 = 2; A1 = 3^2/2 = 4.5 ⇒ ratio 4.5 : 2 = 9 : 4.Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:9 : 4.
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