Students first learn absolute value in middle school as the distance from zero.   So |5| = |-5| = 5.  In high school, absolute value is combined with algebra and inequalities.  

Many specifications can be written with absolute value such as an acceptable measurement within a certain range -- for example 4.75 Volts - 5.25 Volts could be the desired power supply voltage for a computer chip.  This could be expressed as 5 +/- 0.25 Volts and could be written as |x - 5| is less than or equal to .25.  By writing this with an absolute value, we take into account that the amount could be over or under by as much as .25 and still be within spec.

Absolute Value Inequalities on Purplemath 

Solving Absolute Value Graphs on the Graphing Calculator 

Data Sheet for 54LS74 Computer Chip 

Even nontechnical positions like advertising are appreciating quantitative skills according to the New York Times Ad Companies Face a Widening Talent Gap.  The actual Math one learns in school may or may not be used on the job, but the process of learning and doing Math teaches problem solving and critical thinking as well as persistence.  These skills are useful in work and in life.

Why Must I Learn Math? by Mark Karadimos

Why Should We Take Math?

Achieve on Do All High School Students Need Challenging Math?

If you have a question that you would like featured, please send an email to Robin.

You are driving at 50 miles per hour. If you decrease the time it takes you to travel 1 mile by 8 seconds, what is your new speed?

Answer to October's Brain Teaser: 

October 2011 Brain Teaser Solution