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In triangle ABC, DE is parallel to BC where D lies on AB and E on AC. If AD = 2 cm, DB = 3 cm and AE = 4 cm, then EC equals
A5 cm
B8 cm
C6 cm
D10 cm
Answer & Solution
Correct answer: C. 6 cm
1. By the Basic Proportionality Theorem, AD/DB = AE/EC.
2. 2/3 = 4/EC.
3. Cross-multiply: 2 EC = 12, so EC = 6 cm.
_Source: NCERT Class 10 Mathematics, Ch 6 "Triangles", §6.3_
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