In triangle ABC,P and Q are the mid points of AB and AC, resecptively. R is a point on PQ such that PR : RQ = 3 : 5 and QR = 20 cm, then what is the length (in cm) of BC?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3. i.e 64.
Here RQ = 20 cm.
The ratio of PR : RQ = 3 : 5
5x = 20 ⇒ x = 4 cm.
3x = 3 × 4 = 12 cm.
PQ = 20 + 12 = 32 cm.
BC = 2 × PQ (By using mid point theorem)
BC = 2 × 32 = 64 cm.