median
don steward
mathematics teaching 10 ~ 16

Saturday, 28 November 2015

circle: introducing circumference

for a regular baked bean tin size of tin (you need to have one really), which do you think is longer:
twice the height or
the distance round the circumference?

















paper rulers work quite well for practical measuring
this version may need scaling
or use graph paper...



how many times do you think the diameter will wrap around the outside of a circle (the circumference)?






























geogebra applet that links diameter with circumference













several of these questions are adapted from KS3 SATs questions (England)










'satellite' is from a KS3 SAT paper







a similar question to 'rope around the Earth' appeared in William Whiston's book on the Elements of Euclid, dated 1702
he was an English theologian, historian and mathematician

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