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Question
Four alternative answers for the following question is given. Choose the correct alternative.
Two circles of radii 5.5 cm and 3.3 cm respectively touch each other. What is the distance between their centers ?
Options
4.4 cm
8.8 cm
2.2 cm
8.8 or 2.2 cm
Solution
The radii of the two circles are 5.5 cm and 3.3 cm.
If two circles touch each other externally, distance between their centres is equal to the sum of their radii.
∴ Distance between their centres = 5.5 cm + 3.3 cm = 8.8 cm
If two circles touch each other internally, distance between their centres is equal to the difference of their radii.
∴ Distance between their centres = 5.5 cm − 3.3 cm = 2.2 cm
Thus, the distance between their centres is 8.8 cm or 2.2 cm
Hence, the correct answer is 8.8 or 2.2 cm .
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