In ∆ABC, P and Q are the middle points of the sides AB and AC, respectively. R is a point on the segment PQ such that PR : RQ = 1 : 4. If PR = 5 cm, then BC = ?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 50 cm.
PR : RQ = 1 : 4
So, PR = 1 unit = 5 cm
RQ = 4 units = 5 × 4 = 20 cm
PQ = PR + RQ
PQ = 5 + 20 = 25 cm
P and Q are midpoints of AB and AC → PQ is a midline
⇒ PQ = BC
⇒ 25 = × BC
⇒ BC = 50 cm