D.

Distance btw the center of circles = R+r

difference of length between radius = R-r

Please have a look on diagram. Traingale formed by joining the center of circles is right angle triangle.

MN^2 = (R+r)^2 - (R-R)^2

=2(Rr)^1/2

priyankur_saha@ml.com wrote:

Two circles with radius R and r are tangent to each other. If L tangent two circles at M and N point, in terms of R and r, what is the value of MN?

A R+r

B R*r

C (R*r)^1/2

D 2(R*r)^1/2

E (R^2*r^2)^1/2

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