1. Chapter 3 L3-4 Notes: Estimating Sums & Differences

2. Rounding Estimate by rounding each decimal to the nearest whole number, then add the digits. Example:60.7 + 68.5

3. On Your Own… a. 49.59 + 16.22 = b. $41.59 - $19.72 = c. 2.33 + 4.88 + 5.88 =

4. Front-End Estimation To use front-end estimation, add or subtract the front digits. (Front digits are digits before the decimal). Example: 34.6 + 55.3

5. On Your Own… a. 22.35b. 5.45c. $37.92 - 11.14 + 0.57 - $21.62

6. Clustering Estimate by rounding a group of close numbers to the same number. Example: 72.50 68.50 69.75 71.75 +

7. On Your Own… a. 6.99 + 6.59 + 7.02 + 7.44 b. $3.33 + $3.45 + $2.78 + $ 2.99 c. 5.45 + 5.3948 + 4.7999