Similar triangles with perimeter ratio 1:4: If ΔGHI ~ ΔKLM and Perimeter(GHI) : Perimeter(KLM) = 1 : 4 with GH = 2 cm, find the exact length (in cm) of the corresponding side KL.
Aptitude
Area
Difficulty: Easy
Choose an option
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A4 cm
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B8 cm
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C32 cm
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D16 cm
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E2 cm
Answer
Correct Answer: 8 cm
Explanation
Introduction / Context:For similar triangles, any linear dimension (including a side) scales in the same ratio as the perimeters. Hence, the side ratio equals the perimeter ratio.
Given Data / Assumptions:
- ΔGHI ~ ΔKLM.
- Perimeter ratio = 1 : 4 → linear scale = 1 : 4.
- GH corresponds to KL; GH = 2 cm.
Concept / Approach:If k is the scale factor from GHI to KLM, then k = 4 (since perimeters scale by k). Therefore KL = k * GH.
Step-by-Step Solution:
KL = 4 * 2 = 8 cm.Verification / Alternative check:Any other corresponding side would be 4 times its match in ΔGHI; 8 cm is consistent with the 1:4 scale.
Why Other Options Are Wrong:4 cm or 2 cm ignore the 4× scale; 16 cm or 32 cm over-scale.
Common Pitfalls:Using area or volume scaling instead of linear/perimeter scaling.
Final Answer:8 cm