lattice math
posted by marc .
Why should we estimate before solving a problem?
We should estimate before solving a problem to make sure our answer is close to the real answer.
Here's a simple problem.
Suppose we want to find wnat a 6% tax on a $10 purchase would be. When you do the math, the answer depends upon where you place the decimal point when you multiply .06 x $10.
You need to estimate what is a reasonable tax on a $10 purchase  6 cents? 60 cents? 6 dollars?

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