Difficulty: Medium
Correct Answer: 14 cm
Explanation:
Introduction / Context:This question tests the conservation of perimeter (or total wire length) when a wire is reshaped. The wire initially forms a circle, so its length is the circle’s circumference. After reshaping into a rhombus, the same wire length becomes the rhombus perimeter. So, equate circumference of the circle to the perimeter of the rhombus and solve for the circle’s diameter.
Given Data / Assumptions:
Concept / Approach:Compute rhombus perimeter, set it equal to circle circumference, then solve for diameter = (perimeter)/pi.
Step-by-Step Solution:
Step 1: Perimeter of rhombus = 4 * 11 = 44 cm Step 2: This equals circle circumference: pi * d = 44 Step 3: d = 44 / pi Step 4: Using pi = 22/7, d = 44 / (22/7) = 44 * 7 / 22 Step 5: 44/22 = 2, so d = 2 * 7 = 14 cmVerification / Alternative check:If diameter is 14 cm, circumference = pi*d = (22/7)*14 = 44 cm, exactly matching the rhombus perimeter 44 cm. Since wire length is conserved, this confirms the answer.
Why Other Options Are Wrong:
28 cm: would give circumference 88 cm, double the required wire length. 7 cm: would give circumference 22 cm, only half the wire length needed. 3.5 cm: far too small; circumference would be 11 cm. 11 cm: would give circumference about 34.57 cm, not 44 cm.Common Pitfalls:Common mistakes include equating circumference to 2*pi*r but then forgetting to convert to diameter, or using area formulas instead of perimeter/circumference. Another pitfall is assuming the rhombus side equals the circle radius or diameter, which is not implied. Always use the “same wire length” conservation idea.
Final Answer:14 cm
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