# Front End & Rounding Gwendolyn Best Suffolk Public Schools

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• Front End& RoundingGwendolyn BestSuffolk Public Schools

• Estimation

• Can I buy three for \$100?

45

• Can I buy three for \$100?

\$23

• Can I buy 5 for \$50?

The basketball would have to cost ______ or less for me to purchase five of them for \$50.

• Can I buy three for \$20?

\$4.95

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

• + 26 + 1,427 + 216

375Hundreds26Tens1,427Thousands216Hundreds

• Round to the highest place.

375Hundreds40026Tens301,427Thousands1,000216Hundreds200

• After you round, add the numbers! 40030 1000+200

1630

• 88574758 7045 +2110

88574758 7045 + 2110

9000 5000 7000+ 2000

• Between 11,000 and 15,000

Between 16,000 and 20,000

Between 20,000 and 25,000

Between 28,000 and 33,000

900050007000+2000

• 2476542489+ 92

2476542489+ 92

200 7000 500+ 90

• 2007000500+ 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

• 502867321285+ 835

5000 7000 1000+ 800 502867321285+ 835

• Front End Estimation

• FRONT ENDThe 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.

• 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.

• + 26 + 1,427 + 216

37537 0262 01,4271,42 021621 0

• 88574758 7045 +2110

88574758 7045 + 2110

8000 4000 7000+ 2000

• 88574758 7045 +2110

88574758 7045 + 2110

8000 4000 7000+ 2000Draw the line after the first number In each addend.

• Between 11,000 and 15,000

Between 16,000 and 20,000

Between 20,000 and 25,000

Between 28,000 and 33,000

800040007000+2000

• 2476542489+ 92

2476542489+ 92

240 6540 480+ 90

• Estimate to find the best answer. 2406540480+ 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

• 502867321285+ 835

5000 6700 1200+ 800 502867321285+ 835

• 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

500067001200+ 800

13700

• 3,876 5,814 3,176+ 7,895

4,000 6,000 3,000+ 8,000

3,000 5,000 3,000+ 7,000

• 9,876 8,514 6,092+ 3,895

9,000 8,000 6,000+ 3,000

10,000 9,000 6,000+ 4,000

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