Radii of two circles are 6.3 cm and 3.6 cm. State the distance between their centers if :

(i) they touch each other externally,

(ii) they touch each other internally.

Let O be the center of the circle with radius = 6.3 cm and O' be the center of circle with radius = 3.6 cm.

(i) When the two circles touch each other at P externally. O' and O are the centers of the circles. Join O'P and OP.

So, O'P = 6.3 cm, OP = 3.6 cm

Hence, the distance between their centres (O'O) is given by

O'O = O'P + OP = 6.3 + 3.6 = 9.9 cm.

Hence, distance between their centers if they touch each other externally is 9.9 cm.

(ii) When the two circles touch each other at P internally, O and O' are the centers of the circles. Join OP and O'P.

So, O'P = 6.3 cm, OP = 3.6 cm.

Hence, the distance between their centres (O'O) is given by

O'O = O'P - OP = 6.3 - 3.6 = 2.7 cm.

Hence, distance between their centers if they touch each other internally is 2.7 cm.