Do you have trouble making sense of word problems? Try these tips:
1) What is the problem asking you to do?
-- Circle the question or problem statement. This is usually at the end of the problem. (Write an equation?)
-- Is this similar to other problems you have solved? If so, how? (Equations of a line?)
-- What will be the form of the answer? (y = mx + b ? or Ax + By = C ? or something else?)
2) Identify the data.
-- Underline the data in the word problem.
-- Double-underline the units, if specified. (miles, km, number of cows, etc.)
3) Draw a picture (or graph).
-- Make sure you have a good understanding of what is happening in the problem.
4) Write a "math sentence" if appropriate
A final step -- celebrate...
I must admit I was unaware of this controversy, but it makes some sense to stop using the constant pi, and to use a new term, tau, instead. Tau is defined as 2 times pi, which would be 6.283. This is explained in a fun article in a recent Scientific American story:
Tau relates the properties of a circle to the circle's diameter, whereas pi is related to the radius (r). So the equation 2*pi*r, which gives the circumference of the circle based on a measure of the radius, is replaced with the simpler version, tau*diameter, where the diameter is simply twice the radius. I always wondered, when bored in class, why mathematicians used the radius in calculations instead of the diameter. The article cites some of the history of pi, and why that constant was chosen.
Mathematically, it makes no difference. The argument for changing everything to tau is based on...