Monday, April 20, 2015

439: Fraction / Decimal Tic-Tac-Toe

We all know that playing the middle of a tic-tac-toe game ensures that you can never lose if you play it right, but this one seems to be a bit trickier.

Where is the best place to start?


Sunday, April 19, 2015

438: NY Daily Statistics

NY Daily News had this:
Government-hating gun owners are shooting themselves in the foot.

The gun-buying frenzy triggered by the 2012 Sandy Hook school shooting pumped $875 million into federal coffers in 2013 alone, according to Vocativ.com. That’s because the Treasury’s Alcohol and Tobacco Tax and Trade Bureau collects a 10% tax on ammo sales and a nearly 10% tax on gun sales. The tax revenue on guns and ammo reached an all-time high the year after the Sandy Hook Elementary School massacre, which left 27 students and teachers dead and triggered fears of stricter gun laws.

The roughly $255 million in tax revenue on ammunition alone brought in by the feds in 2013 was nearly double the 1991 tax receipts for handguns, long guns and ammo combined, according to Vocativ.

Is that graph properly done?
Is it misleading?
Is the data itself misleading?
source.

Saturday, April 18, 2015

437: Specificity and Clarity in Math

Mathematical Grammar ... I think a comma might be necessary in #2, maybe two of them. What do you think, students?

436: Whiteboards at NCTMBoston


435: Interesting Question from NCTM Boston


Friday, April 17, 2015

434: Integer Quotient

Is it possible to find a positive integer value of  n so that this quotient is an integer?

Thursday, April 16, 2015

433: Do We Need to Feed the Meter?






If you are parked during any part of the time indicated, then you need to pay, even if it's only for a few minutes at the beginning or end of your shopping. (If you only are there for the five minutes between 8:00 and 8:05, you only pay a pro-rated fee.)


If you park at any random time and leave your car there for an hour, are you more likely to pay or more likely to not pay?


source.