Instead of posting this innocent little combinatorial problem to Twitter like I've been doing for the past 2 years, I decided to post it here so my readers will know MathNotations is not extinct!
Comments about this problem:
1) What would be an easier variation you might first pose? Oct 2009 SAT, Prob 17, "grid-in"!
2) To those who have been teaching these types for awhile, SHARE your strategies!
3) A Black Box Soln:
100-(50+33-16)=33
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Tuesday, January 15, 2013
How many positive integers less than 101 are not div by 2 and not div by 3?
Posted by Dave Marain at 3:09 PM
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