1 / 7

3-4: Estimating Sums and Differences

3-4: Estimating Sums and Differences. Rounding Clustering Front-end-estimating . Rounding. Most of the time, you will be asked to round to the nearest whole number. Round to the ones place, and drop the decimal part of your number. Example: Estimate the sum of 10.93 and 3.25. 11.

micol
Download Presentation

3-4: Estimating Sums and Differences

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 3-4: Estimating Sums and Differences Rounding Clustering Front-end-estimating

  2. Rounding • Most of the time, you will be asked to round to the nearest whole number. • Round to the ones place, and drop the decimal part of your number.

  3. Example: Estimate the sum of 10.93 and 3.25. 11 11.00 10.93 3.00 3 3.25 + 14

  4. Clustering • Use when all numbers are close to the same amount • If so, round each number to the same number. • Then multiply • Ex) $2.44 + $1.86 + $2.11 + $1.70 $2 x 4 = $8

  5. Front End Estimation • Add or subtract the values of the digits in the front place or left-most place value. • Usually gives a sum that is less than the actual sum.

  6. Example 5.45 9.89 3.53 6.03 Front-end: 5 + 9 + 3 + 6 = 23 + About 23

  7. Try P152 # 1-9 • 0+1 = 1 • $15 + $32 = $47 • 4 – 3 = 1 • 60 – 20 = 40 • 3 x 5 = 15 • $3 x $1 = $3 • C • 100 + 500 = 600 • $400 - $100 = $300 The above image is a royalty free picture provided by http://www.bigfoto.com

More Related