Decimal Rounding Given Place Value Jen Kershaw, M.ed Kimberly Hopkins Jen Kershaw Kaitlyn Spong
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AUTHORS Jen Kershaw, M.ed Kimberly Hopkins Jen Kershaw Kaitlyn Spong
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Chapter 1. Decimal Rounding Given Place Value
C HAPTER
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Decimal Rounding Given Place Value
In this concept, you will learn how to round to a given place value.
Kalisha has a small bag that weighs 0.879 pounds. She is filling out a form that only allows her to write the weight to the hundredths. The form tells her to round to the nearest hundredths, but she doesn’t know how to do that. How can she round 0.879 to the nearest hundredths, and what number should she write on the form? In this concept, you will learn how to round to a given place value.
Rounding Decimals to a Given Place Value
You can use place value to help you round numbers to the nearest whole or tenths, hundredths, thousandths, etc. Let’s look at an example. Round 0.345 to the nearest tenth. To help you with this, put the number in the place value chart.
TABLE 1.1: Tens
Ones .
Tenths
Hundredths
Thousandths
3
4
5
Ten Thousandths
The 3 is in the tenths place. The 4 is the digit to the right of the tenths place. 4 is less than 5, so leave the 3 alone. The answer is 0.3 is the nearest tenth. You could have put zeros to represent the other digits, but that isn’t necessary. Let’s look at another example. Round 0.567 to the nearest hundredth. To help with this, let’s use the place value chart again.
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TABLE 1.2: Tens
Ones .
Tenths
Hundredths
Thousandths
5
6
7
Ten Thousandths
The 6 is in the hundredths place. The 7 is the digit to the right of the hundredths place. Since 7 is 5 or greater, round up to the next digit. The 6 becomes a 7. The answer is 0.57. Notice that the five is included because it is to the left of the place you are rounding. Examples Example 1
Earlier, you were given a problem about Kalisha and her bag. Round 0.879 to the nearest hundredths for her and write the value that she should put on the form. First, put the number in the place value chart.
TABLE 1.3: Tens
Ones .
Tenths
Hundredths
Thousandths
8
7
9
Ten Thousandths
Next, determine if the number to the right of the hundredths place is 5 or greater. Yes, it is greater. Then, round the number in the hundredths place to the next value. 0.88 The answer is 0.88. Kalisha should write 0.88 on the form. Example 2
Round 0.221 to the nearest tenth. First, put the number in the place value chart.
TABLE 1.4: Tens
Ones .
Tenths
Hundredths
Thousandths
2
2
1
Next, determine if the number to the right of the tenths place is 5 or greater. No Then, leave the number in the tenths place the same. 0.2 2
Ten Thousandths
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Chapter 1. Decimal Rounding Given Place Value
The answer is 0.2. Example 3
Round 0.892 to the nearest tenth. First, put the number in the place value chart.
TABLE 1.5: Tens
Ones .
Tenths
Hundredths
Thousandths
8
9
2
Ten Thousandths
Next, determine if the number to the right of the tenths place is 5 or greater. Yes Then, round the number in the tenths place to the next value. 0.9 The answer is 0.9.
Example 4
Round 0.632 to the nearest hundredth. First, put the number in the place value chart.
TABLE 1.6: Tens
Ones .
Tenths
Hundredths
Thousandths
6
3
2
Ten Thousandths
Next, determine if the number to the right of the hundredths place is 5 or greater. No Then, round the number in the hundredths place to the next value. 0.63 The answer is 0.63. Example 5
Round 0.1238 to the nearest thousandths. First, put the number in the place value chart.
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TABLE 1.7: Tens
Ones .
Tenths
Hundredths
Thousandths
1
2
3
Ten Thousandths 8
Next, determine if the number to the right of the thousandths place is 5 or greater. Yes Then, round the number in the thousandths place to the next value. 0.124 The answer is 0.124. Review
Round according to place value. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
Round .45 to the nearest tenth Round .67 to the nearest tenth Round .123 to the nearest tenth Round .235 to the nearest hundredth Round .567 to the nearest hundredth Round .653 to the nearest hundredth Round .2356 to the nearest thousandth Round .5672 to the nearest thousandth Round .8979 to the nearest thousandth Round .1263 to the nearest thousandth Round .056 to the nearest tenth Round .0091 to the nearest hundredth Round .0918 to the nearest tenth Round .0023 to the nearest thousandth Round .1368 to the nearest hundredth
Review (Answers)
To see the Review answers, open this PDF file and look for section 3.12. Resources
MEDIA Click image to the left or use the URL below. URL: https://www.ck12.org/flx/render/embeddedobject/176208
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