April 2010 Brain Teaser Answer

Using all the digits from 0,1,2...9, form two 5-digit numbers so that their sum is the

a)smallest sum:   34047


One example:  20468 + 13579
Another example is: 10468 + 23579
 
You cannot have a leading zero (the number cannot start with a zero) so for the least sum, start with 1 for the first number and 2 for the second number. Then make 0 the second digit of one of them and 3 the other second digit.  Then continue with 4 and 5 and so on.

b)greatest sum: 183951

One example is: 97531 + 86420
Another example is: 87531 + 96420

For the greatest sum: First digits 8 or 9, Second digits 6 or 7 and so on.

Millions and Billions

New York Hall of Science

Career and College Ready

According to this Washington Post article: http://voices.washingtonpost.com/answer-sheet/no-child-left-behind/what-is-being-college-and-care.html, only 23% of college students do not remediation.  The article quotes an ACT spokeswoman "Readiness for college means not needing to take remedial courses." 

High schools and society would do well to focus on college and career readiness in addition to graduation rates.  While there is no high school exit exam, only 60% of high school graduates could pass the GED (according to the GED).

Preparing Math Teachers

Financial Literacy as a School Subject

NYT article on Financial Literacy in School
Often students and parents will ask "When I am ever going to use this Math?".  Studying trig and algebra will make you smarter and therefore you will have the capacity to understand Finance and Economics.  An excellent topic mentioned in the article is Time Value of Money.  A good example is:
How much will you have if you invest $100 for 3 years at 10% compounded annually?
This question inspires dialogue and learning on interest rates, banking, decimals, percents, exponents as well as opening a window into understanding the way the world works.

Identifying Problems...ok Math Opportunities

Metacognition (thinking about thinking) is the feedback loop or the "little voice in your head that you hear when you do Math -- such as add 4 to each side and divide both sides by 2".

Self-awareness of knowledge and skills can be achieved by categorizing Math problems into types of problems.  The ability to identify problem types can refine learning and bring clarity while increasing the enjoyment and flow of Math opportunities.  This is especially important in Math as gauging the level of challenge can help students know what to study and how to invest their time and energy under peak perfromance coniditions (tests).

It is a problem that they call them problems --  so how about Math opportunities?

Math can Build Non-Cognitive Skills too!

Studying Math may seem like a purely academic endeavor but it improves focus, persistence and self-advocacy which are takeaways that are "life skills".  This article quotes Dan Pink author of Drive on parents focusing on academics at the expense of "life skills" but school can also fuel these skills and talents that can then be applied to any endeavor whether academic, athletic or otherwise.
New York Times on Determination and Deliberate Practice