This task builds off of the skill of rounding to the nearest ten and hundred in third grade. Aligns with CCSS.Math.Content.3.NBT.A.1 Use place value understanding to round whole numbers to the nearest 10 or 100.

This site from the University of California provides a lengthy and intelligent discussion of sig figs, absolute and relative precision, accuracy, precision in calculations, rounding off, and the whole shooting match of how we report what...

If you are looking for a website that explains and defines the basics of mental multiplication with helpful hints then you have arrived at an excellent resource. There are even practice problems at the very end of the lesson.

[Free Registration/Login may be required to access all resource tools.] Estimate products and quotients of fractions and mixed numbers.

BBCi presents a test prep review ("revision") section on significant digits and on approximating an answer by rounding in order to work with an easy number. Click on "Test Bite," on the last page to get an interactive quiz.

You may print off addition, subtraction, multiplication, division, averages, fraction, and other miscellaneous worksheets that are related to mathematics. On the left hand side of this page you will also find links to other subjects,...