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Pinis the relationship of a circle’s circumference to its diameter. Nonmatter how large or small a circle is, the proportion of the distancenaround the circle to the distance across its widest part is EXACTLYnthe same!
Pinis the relationship of a circle’s circumference to its diameter. Nonmatter how large or small a circle is, the proportion of the distancenaround the circle to the distance across its widest part is EXACTLYnthe same!n
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nThatnexact number starts off 3.14159265…and goes on for bajillions ofnnon-repeating digits. Because pi starts with 3.14, we celebrate PinDay on 3/14, or March 14th. n
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nButntoday is not that date. Why are we celebrating Casual Pi Day today? n
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nWell,nthe other name for the day gives us a hint—it’s Pi ApproximationnDay.
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It’snhard to be exact about pi when the decimal digits go on forever (andndon’t even repeat). So we have to use approximate numbers when wenactually use pi, and a really approximate way of expressing thenapproximation is the fraction 22/7. And that’s why today, the 22ndnday of the 7th month, is Pi Approximation Day!
It’snhard to be exact about pi when the decimal digits go on forever (andndon’t even repeat). So we have to use approximate numbers when wenactually use pi, and a really approximate way of expressing thenapproximation is the fraction 22/7. And that’s why today, the 22ndnday of the 7th month, is Pi Approximation Day!n
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nUsena calculator to see what 22 divided by 7 is. How many decimal placesnmatch pi?
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nBynthe way, you can get a picture of pi being all casual and summery onna T-shirt or mug here.
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nApproximate,nashmoximate!
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nWhennwe are doing mental math or solving real-life problems in our heads,nwe often don’t need the exact answer. Instead, we can use just annapproximation of the right answer. And we do this bynestimating—rounding off and THEN adding or multiplying or whatevernwe are trying to do…
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nPracticenyour estimation skills with these PBS games or these Gamequarium games.
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nAlsonon this date:
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nRevolution Day in the Gambia
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nNational Tree Planting Day in the Central African Republic
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nBirthday of the king of Swaziland
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nAnniversary of three first-flights-around-the-world
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