Welp, looking at the number: 66
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The second digit "6" is up to or more than 5.
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So, we can clearly round it up.
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In this case, we are rounding to the nearest hundredth.
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Hm, 100 is pretty close to 66.
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We can now say that the nearest hundredth is 100.
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BAM! *drops mic*
Square root it to cancel out the 2
<span> 1.7676 Feet is the diameter</span>