In, two similar triangles \( \Large \triangle \) ABC and  \( \Large \triangle \) DEF, DE = 3 cm, EF = 5 cm, DF = 4 cm and BC = 20 cm, then length of AB is equal to


A) 15 cm

B) 12 cm

C) 10 cm

D) 6 cm

Correct Answer:
B) 12 cm

Description for Correct answer:



From similar triangles ABC and DEF

\( \Large \frac{AB}{BC} = \frac{DE}{EF} \)

\( \Large \therefore \frac{AB}{20} = \frac{3}{5} \)

=> \( \Large AB = \frac{3 \times 20}{5} \) = 12 cm.


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