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# Monthly Archives: June 2010

## Right answers for the wrong reasons

Here’s a recent xkcd which as a math educator I found particularly funny. Some questions for my readers: What numbers besides 3 and 9 would “work” here? Do you have any particularly funny or interesting stories of students getting something … Continue reading

## Optimal change-carrying

Recently Michael left the following challenge in a comment: I’ve been trying to optimize my change-carrying habits. What is the smallest amount of quarters, dimes, nickels and pennies one can carry while still being able to give perfect change (two … Continue reading