In triangle PQR, C is the centroid. PQ = 30 cm, QR = 36 cm and PR = 50 cm. If D is the midpoint of QR, then what is the length (in cm) of CD?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. (4√86)/3
Using apply theorm:
2(OD2 + PD2) = PQ2 + PR2
⇒ 2(182 + PD2) = 302 + 502
⇒ 2(324 + PD2) = 900 + 2500
⇒ 2PD2 = 2752
⇒ PD = 4√86
Hence,
CD = PD/3 = 4√86/3 cm