To: Teacher2Teacher Public Discussion
It is not often that you find someone who is aware that if you double the diameter of a sphere (or apple, plum, cherry) you will get 8 times as much. When it comes to hot dogs, where the length remains the same, but the diameter gets cut in half, then the factor will be 1/4 as much. In the sphere we double 3 dimensions whereas in a cylinder, if we hold the length constant, we only double two dimensions. Students could bring in a collection of apples of various sizes and have the students weigh and measure the diameters using s tool or measure the circumference and calculate the diameter. When I was a kid, I had the opportunity to pick plums, apples, cherries and currents. It doesn't take long to pick a bucket of apples. You can pick a bucket of plums in about 8 times as long as it takes for apples. For Cherries, it takes about 64 times as long to pick a bucket of them as it does for apples. Imagine how long it takes to pick a bucket of currents which are about half the size of cherries. When you by cantaloupe by the piece, you will get lot more by picking out the biggest in the store or patch. If you have noticed, manufacturers have reduced the diameter of lots of items in the past 30 or 40 years. They learned their math well.
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