Chapter 3 L3-4 Notes: Estimating Sums & Differences

Rounding Estimate by rounding each decimal to the nearest whole number, then add the digits. Example:

On Your Own… a = b. $ $19.72 = c =

Front-End Estimation To use front-end estimation, add or subtract the front digits. (Front digits are digits before the decimal). Example:

On Your Own… a b. 5.45c. $ $21.62

Clustering Estimate by rounding a group of close numbers to the same number. Example:

On Your Own… a b. $ $ $ $ 2.99 c