1. Front End & Rounding Gwendolyn Best Suffolk Public Schools

2. Estimation The next few slides will help you test your estimation skills.

3. Can I buy three for $100? 45

4. Can I buy three for $100? $23

5. Can I buy 5 for $50? The basketball would have to cost ______ or less for me to purchase five of them for $50.

6. Can I buy three for $20? $ 4.95

7. Rounding to the highest Place Value Round each number to its highest possible place value. Some numbers will be rounded to ten- thousands, thousands, hundreds, or tens.

8. 375+ 26 + 1,427 + 216 375Hundreds 26Tens 1,427Thousands 216Hundreds

9. Round to the highest place. 375Hundreds400 26Tens30 1,427Thousands1,000 216Hundreds200

10. After you round, add the numbers! 400 30 1000 +200 1630

11. 8857 4758 7045 +2110 8857 4758 7045 + 2110 9000 5000 7000 + 2000

12. Between 11,000 and 15,000 Between 16,000 and 20,000 Between 20,000 and 25,000 Between 28,000 and 33,000 9000 5000 7000 +2000

13. 247 6542 489 + 92 247 6542 489 + 92 200 7000 500 + 90

14. 200 7000 500 + 90 A little less than 7,000 A little less than 8,000 A little more than 8,000 A little more than 10,000

15. 5028 6732 1285 + 835 5000 7000 1000 + 800 5028 6732 1285 + 835

16. Front End Estimation

17. FRONT END The name of this strategy gives you a clue about how it is used. The word FRONT should remind you that you are only concerned with the front portion of the number. Many people think this strategy is easier than rounding to the highest place value.

18. 4,32 0 74 0 2,39 0 + 2 0 4,329 748 2,398 + 28 Draw a line through your list of numbers so that you have at least one digit from each addend in front of (before) the line. Change all numbers after the line to zeros. All numbers before the line stay the same.

19. 375+ 26 + 1,427 + 216 375 37 0 26 2 0 1,427 1,42 0 216 21 0

20. 8857 4758 7045 +2110 8857 4758 7045 + 2110 8000 4000 7000 + 2000

21. 8857 4758 7045 +2110 8857 4758 7045 + 2110 8000 4000 7000 + 2000 Draw the line after the first number In each addend.

22. Between 11,000 and 15,000 Between 16,000 and 20,000 Between 20,000 and 25,000 Between 28,000 and 33,000 8000 4000 7000 +2000

23. 247 6542 489 + 92 247 6542 489 + 92 240 6540 480 + 90

24. Estimate to find the best answer. 240 6540 480 + 90 A little more than 7,000 A little more than 8,000 A little less than 9,000 A little less than 10,000 7350

25. 5028 6732 1285 + 835 5000 6700 1200 + 800 5028 6732 1285 + 835

26. Estimate and choose the most reasonable answer. Between 11,000 and 15,000 Between 16,000 and 20,000 Between 20,000 and 25,000 Between 28,000 and 33,000 5000 6700 1200 + 800 13700

27. 3,876 5,814 3,176 + 7,895 4,000 6,000 3,000 + 8,000 3,000 5,000 3,000 + 7,000

28. 9,876 8,514 6,092 + 3,895 9,000 8,000 6,000 + 3,000 10,000 9,000 6,000 + 4,000