1. Lesson 17

2.  Addends- The numbers that are being added together.  Reasonable- Does it make sense?

3.  First we find the nearest hundred.  362 ~ 400 159~200  Then we round to the nearest ten.  362~ 360 159~ 160  Then we round to the closest 50.  360~350 159~150

4. 362 + 159 400 + 200 = 600 (Rounding to nearest hundred) 360 + 160 = 520 (Rounding to nearest ten) 350 + 150= 500 (Rounding to nearest 50) Which method of rounding will give the closest sum? Talk to your neighbor about your answer.

5.  (A) 349 + 145 (B) 352 +145 (C) 352 + 151  Round to the nearest hundred  Round to the nearest ten  Round to the nearest 50  What did you realize about these numbers?  Find the exact value of the sums.

6.  296 + 609  Round to the nearest hundred  Round to the nearest ten  Round to the nearest 50  What did you realize about these numbers?  Find the exact value of the sums.