January 25th, 2011 by Dan Meyer
Sorry to be all post-y today but reader Ryan Bavetta sent in a hot tip and I had to jump on it before Drudge did. Here's Obama delivering his State of the Union address. Ryan says, "I don't think they got the sizes of the circles right."
So I go all Woodward and Bernstein with my compass and protractor. I measure off the diameters.
The ratio of the diameters is 2.45, which means the ratio of the areas is going to be (2.45)^2 or 6.00. But the ratio of America's GDP to China's GDP (14.6T/5.7T) is only 2.56! The US circle is too big! What's the progressive propaganda machine trying to sell us here?!
Here's how it should have looked:
For Classroom Use
I think you have to get rid of one of the quantities, ask the students to determine it, show them the full SOTU screenshot, and then encourage them to marvel at the difference. You can give them Obama's circle and ask them to tell you what that should make the GDP.
Or you can give them the GDP and ask what that should make the circle.
I don't know how to get excited about the difference when Jon Stewart's probably trying to call my booking agent right now.
The problem archive, including:
- the original image,
- the image without the GDP,
- the image without the circle,
- video from the speech itself,
- an extension problem.
2011 Feb 16: Updated to add higher-resolution images, video from the speech itself, and an extension problem.