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© 2007 M. Tallman

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Find your number. Look right next door. 35 Step 1: Circle the digit in the place that you must round to. Step 2: Draw an arrow to the place on the right. Round to the nearest thousands place., 4 6

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000 3 4 6 Step 1: Circle the digit in the place that you must round to. Step 2: Draw an arrow to the place on the right. Step 3: If the number is four or less, then the circled number stays the same. Step 4: All numbers to the right of the circled number become zeros. 4 or less, just ignore. 3 is less than 4 Just Ignore! 5, Round to the nearest thousands place.

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© 2007 M. Tallman 7 Find your number. Round to the nearest hundreds place. Look right next door. Step 1: Circle the digit in the place that you must round to. Step 2: Draw an arrow to the place on the right. 53, 6

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© 2007 M. Tallman 0 0 6 7 65 4 or less, just ignore. 5 or more, add 1 more. 7 is not less than 4 Step 1: Circle the digit in the place that you must round to. Step 2: Draw an arrow to the place on the right. Step 3: If the number is four or less, then the circled number stays the same. Step 4: If the number is 5 or greater, then add 1 to the circled number. Step 5: All numbers to the right of the circled number become zeros. Round to the nearest hundreds place. 5 + 1 = 6 3,

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© 2007 M. Tallman When to use estimation… WWhen an exact answer is not needed. WWhen you need to compute a problem quickly. TTo check your work.

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486 + 130 5 1 + = 6 Step 1: Rounding is always first. Decide which place to round to. Step 2: Round each addend to the hundreds place. 0 00 0 The actual answer is 616, so our estimation is pretty accurate. Step 3: Now you can add 500 and 100 mentally.

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© 2007 M. Tallman 5,387 + 386 5,000 400+ = 5,400 Step 1: Rounding is always first. Decide which place to round to. Step 2: Round the first addend to the thousands place and the second addend to the hundreds place. Step 3: Now you can add 5,000 and 400 mentally. The actual answer is 5,773, so our estimation is pretty accurate Rounding Tip: The lower the place, the more accurate the answer. However, if you round too low, your problem may be more difficult to solve. Rounding Tip: The higher the place, the easier your problem will be to solve. However, your answer may not be as accurate.

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© 2007 M. Tallman 5,400 5,387 + 386 5,000 400+ = 5,400 Step 1: Rounding is always first. Decide which place to round to. Step 3: Now you can add 5,400 and 400 mentally. 5,800 Step 2: Round the first addend to the thousands place and the second addend to the hundreds place.

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© 2007 M. Tallman 44,897 + 26,578 40,000 30,000 + = 70,000 Step 1: Rounding is always first. Decide which place to round to. Step 2: Round each addend to the ten thousands place. Step 3: Now you can add 40,000 and 30,000 mentally. The actual answer is 71,475, so our estimation is pretty accurate.

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© 2007 M. Tallman $8.67 + $6.75 $9.00 $7.00 + = $16.00 Step 1: Rounding is always first. Decide which place to round to. Step 2: Round each addend to the nearest dollar. Step 3: Now you can add $9.00 and $7.00, mentally. The actual answer is $15.42, so our estimation is pretty accurate.

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© 2007 M. Tallman 1. $21.89 + $6.78 5,000 600 100+ 500 = 1,200 + 700 = $27.00 4. 4,897 + 598 3. 145 + 467 Estimate Each Sum 2. 467 + 721 $20.00 + $7.00 = 5,600 + 600 =

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© 2007 M. Tallman 5. 897,965 + 12,854 800,000 10,000 6,000+ 4,000 = $350.00 $50.00 + $300.00 = 910,000 8. 765,987 + 46,980 7. 5,897 + 4,465 Estimate Each Sum 6. $47.90 + $271.87 900,000 + 10,000 = 850,000 + 50,000 =

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© 2007 M. Tallman 9. $8.75 + $3.98 200,000 38,000 8,000+ 30,000 = $900.00 $400.00 + $500.00 = $13.00 12. 167,876 + 446,987 11. 8,321 + 32,432 Estimate Each Sum 10. $376.98 + $547.98 $9.00 + $4.00 = 600,000 + 400,000 =

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