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Question
Radii of two circles are 6.3 cm and 3.6 cm. State the distance between their centres if:
- they touch each other externally,
- they touch each other internally.
Solution
Radius of bigger circle = 6.3 cm
And radius of smaller circle = 3.6 cm
i.
Two circles are touching each other at P externally. O and O' are the centers of the circles. Join
OP and O'P
OP = 6.3 cm, O'P = 3.6 cm
Adding,
OP + O'P = 6.3 + 3.6 = 9.9 cm
ii.
Two circles are touching each other at P internally. O and O' are the centers of the circles. Join
OP and O'P
OP = 6.3 cm, O’P = 3.6 cm
OO’ = OP – O’P = 6.3 – 3.6 = 2.7 cm
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`square` = `square`
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