Chicago Parent was out and about at the Chocolate Fest in Long Grove this weekend, and one of our contests was a “Guess-how-many-gumballs-are-in-this-jar.” Now, we run these pretty frequently and we’ve seen our share of goofy methods. But this one, so thoroughly un-goofy — and, by the way, producing an answer with a 1.1 percent margin of error, wins.
By the way, the correct answer was 803. Sadly, other people guessed 800, so this entrant, a teenage boy, didn’t win. But somewhere in Chicagoland, a geometry teacher can rest easy.
Just to break it down:
---> C = circumference of the jar ---> H = height of the jar
—> formula for the circumference of a circle
—> calculates radius of the jar’s cross-section
---> formula for volume of a cylinder (SATs, here he comes!) --->some nifty arithmetic
—> an answer with a 1.1 percent margin of error. Not too shabby.