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The smaller gray circles inscribed within the larger circle have equal sizes.

They are all tangent to one another as well as to the larger circle. If the smaller circles each have a radius of 20, what is the radius of the larger circle?

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bubba-math profile image59

Best Answer Jim Bob (bubba-math) says

4 years ago
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ib radmasters profile image60

ib radmasters says

4 years ago
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tussin profile image60

I'M BANNED Y'ALL!!!!!!!!!! (tussin) says

3 years ago
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  • bubba-math profile image

    Jim Bob (bubba-math) 3 years ago

    Descartes' Theorem. That's a much faster way to solve it for sure.


Larry Wall says

4 years ago
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  • Larry Wall 4 years ago

    I accept the answer, I just wish you would tell me where I was wrong in my approach. I still contend that the smaller circles had no impact on the radius of the larger circle. Would the radius be different if the smaller circles were not there?

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normal says

4 years ago
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    TR Smith (calculus-geometry) 4 years ago

    You're on the right track. You do need to examine what's going on in the center of the circle and at the points of tangency.