In response to Who Needs Math? in the Education Life of the NYT in early February, this high school student totally gets it!!!

# All posts by mathconfidence

# The New SAT Reading Section Looks Harder

# January 2016 Brain Teaser Solution

Q: A swindler showed an honest man a six sided die. If the man rolled a ONE, he wins, and gets back twice the amount of his bet. If not, the swindler keeps the bet. “But…my chances are only one out of six,” retorted the man. “True,” grinned the swindler, “But I’ll give you three tries to get a one.” The man considered if I have 3 tries, each try has a 1/6 chance of winning, so my chances of winning are 3/6 or 1/2. Is the bet really fair? If not, what are the chances of the man winning?

A: 91/216

You cannot just add 1/6 + 1/6 +1/6 so 1/2 is incorrect. The probability of not getting a 1 is 5/6 (there are 6 sides and the other possible outcomes are 2, 3, 4, 5 or 6). The probability of no 1s in 3 throws is 5/6 x 5/6 x 5/6 = 125/216 which is the probability of the swindler winning. So the probability of the man winning is 1 – 125/216 = 216/216 – 125/216 = 91/216.

# Survey: How hard is freshman year algebra?

Pre-Uber it was Integrated Algebra, see below for current freshman-year algebra

Common Core Algebra I Regents

**Pre-Uber, was getting a cab in NYC harder than freshman-year algebra?**

Please vote HERE

Glad to see the Math in the tag line “Helping aggrieved consumers for more than six-tenths of a decade”

# Should We Tell Them?

“The rule for the square of a binomial”: Spotted with a 12th grader Homework on Pearson’s My Math Lab

Should we tell students exactly what to do?

Categorization is one of the most important skills in Math and one of the most important takeaways for future Math classes and in general.

The question above creates teaching and learning questions:

“Should we tell students what to do based on rules?”

“Can students (even) remember rules?”

“What would be the answer to this problem?”