What's New - April, 2015
April 13, 2015: Here's an interesting little puzzle that requires some human thought to solve efficiently:
A farmer tells his son to select five watermelons to take to market. Because the watermelons are sold by weight, they must be put on a scale before the trip to town, but the son makes a small mistake and weighs them in pairs. Here are the weights he comes up with, in pounds: 20, 22, ,23, 24, 25, 26, 27, 28, 30, 31. How much does each of the watermelons weigh? (Source: Sit & Solve® Brainteasers (Sit & Solve® Series)
The Weighing Watermelons program posted today implements the solving strategy.
April 19, 2015:
A buddy of mine is designing a Veteran's Day monument which will consist of
panels representing the Armed Forces services and aligned in such a way that the
sun will cast a shadow on the memorial plaque on November 11 at 11:AM. At
his location, he thought that the sun would cast the shadow again in February
when the the sun will be at the same altitude at that hour. I took
advantage of the opportunity to educate him about the "analemma" figure 8
shape of the sun's path through the sky and assure him that the February sun at
11 AM will be about 10 degrees further East than the November path. I
updated AstroDemo Version 2.0, our
Astronomy unit test program, with an "animated" analemma. That option helped me
determine that at 11:11 AM in Lucedale, MS, the crossing point of the figure 8
occurs on February 12 as days are getting longer and August 29 on the way back
down, so no problem for Jim's project!
April 29, 2015: Three points are placed randomly on the circumference of a circle. What is the probability that all three points lie within same semicircle? Check out Circular Reasoning to verify your answer.