In a ∆ PQR, ∠RPQ = 90°, PR = 6 cm andPQ = 8 cm,

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In a ∆ PQR, ∠RPQ = 90°, PR = 6 cm andPQ = 8 cm, then the radius of the circumcircle of ∆ PQR is

1. 5 cm
2. 3 cm
3. 4 cm
4. 4.5 cm

Correct Option: A

On the basis of question we draw a figure of an right angled triangle ,

Here , ∠RPQ = 90°, PR = 6 cm andPQ = 8 cm,
From ∆QPR ,
∴ RQ = √PR² + PQ²
RQ = √6² + 8² = √36 + 64
RQ = √100 = 10 cm
∴ Circum-radius = 10 ÷ 2 = 5 cm