# In the given figure, QR is a common tangent to the given circles, touching externally at the point T. The tangent at T meets QR at P. If PT = 3.8 cm then the length of QR isA. 1.9 cmB. 3.8 cmC. 5.7 cmD. 7.6 cm

Let the bigger circle be C1 and Smaller be C2,

Now,

PQ and PT are two tangents to circle C1,

PT = QP

[Tangents drawn from an external point are equal]

QP = 3.8 cm

[ As PT = 3.8 cm is given]

Also,

PR and PT are two tangents to circle C2,

PT = PR

[Tangents drawn from an external point are equal]

PR = 3.8 cm

[ As PT = 3.8 cm is given]

QR = QP + PR = 3.8 + 3.8 = 7.6 cm

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