MAA MinuteMath: July 1, 2009

Wednesday, July 1, 2009

July 1, 2009

Call a number "prime-looking" if it is composite but not divisible by 2,3, or 5. The three smallest prime-looking numbers are 49, 77, and 91. There are 168 prime numbers less than 1000. How many prime-looking numbers are there less than 1000?

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Exercise your mind daily with a problem from the AMC-8, AMC-10, or AMC-12, provided by Mathematical Association of America's American Mathematics Competitions.

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Curriculum Inspirations is a collection of resources for Middle and High School Math Teachers that demonstrate practical ways to engage students in the lively exploration of mathematics and mathematical thinking using problems from America’s longest-running and most successful mathematics competition. Developed by James Tanton, these resources include Ten Problem Solving Strategy Essays and Curriculum Bursts.

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