Blue Balls Bounce
(page 63)

(January 2008) Here is a solution from four eighth grade students: Bridgette, James, Brittni, and Jessica. I think they're in West Virginia; these may be some of the same students who corrected a solution to Tuppins.

We figured out a solution for Blue Balls Bounce. If you dropped them both from 50 they would bounce to the same height, which is 45 centimeters. We figured this out because if you drop the the Linyaball from 50 all you do is subtract five, which is 45. If you dropped the Proportiaball from 50 and subtract 10% it is also 45. You have to figure out what number five is ten percent of.

The Proportiaball bounces higher than the Linyaball on all bounces that are less than 50 centimeters in height.

If you drew a line graph of each of the balls bounces, where the lines intercepted is where they bounced the same height.

Thank you, Bridgette, James, Brittni, and Jessica! Another "first solution!"

So, readers, what do you think? Did they answer the questions correctly? Did they answer all of the questions posed in the problem? Can you understand their thinking from what they wrote?

Why does the Proportiaball bounce higher for all bounces under 50 cm?

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