How to Round a Number to the Nearest Tenth (1 Decimal Place)

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1 How to Round a Number to the Nearest Tenth (1 Decimal Place)

2 Place Value Review ths Notice the decmal point. All places to the right of the decimal end with “ths”

3 For you notebook (copy this):
Rounding Decimals: to round a decimal to a given place value, look at the digit in the place to the right. If the digit is 4 or less, round down. If the digit is 5 or greater, round up.

4 First look at the value of the digit in the hundredths column
4.675 Has 7 hundredths

5 First look at the value of the digit in the hundredths column
4.675 Has 7 hundredths 5.85 Has 5 hundredths

6 First look at the value of the digit in the hundredths column
4.675 Has 7 hundredths 5.85 Has 5 hundredths Has 2 hundredths 3.7298

7 First look at the value of the digit in the hundredths column
4.675 Has 7 hundredths 5.85 Has 5 hundredths Has 2 hundredths 3.7298 Has 3 hundredths

8 You round down to the nearest tenth if the hundredths digit is 0,1,2,3 or 4.
3.726 is rounded down to 3.7

9 You round down to the nearest tenth if the hundredths digit is 0,1,2,3 or 4.
3.726 is rounded down to 3.7 4.23 is rounded down to 4.2

10 You round down to the nearest tenth if the hundredths digit is 0,1,2,3 or 4.
3.726 is rounded down to 3.7 4.23 is rounded down to 4.2 is rounded down to 17.5

11 You round down to the nearest tenth if the hundredths digit is 0,1,2,3 or 4.
3.726 is rounded down to 3.7 4.23 is rounded down to 4.2 is rounded down to 17.5 is rounded down to 120.6

12 You round down to the nearest tenth if the hundredths digit is 0,1,2,3 or 4.
3.726 is rounded down to 3.7 4.23 is rounded down to 4.2 is rounded down to 17.5 is rounded down to 120.6 is rounded down to 45.4

13 You round up to the nearest tenth if the hundredths digit is 5,6,7,8 or 9.
4.67 is rounded up to 4.7

14 You round up to the nearest tenth if the hundredths digit is 5,6,7,8 or 9.
4.67 is rounded up to 4.7 is rounded up to 5.9

15 You round up to the nearest tenth if the hundredths digit is 5,6,7,8 or 9.
4.67 is rounded up to 4.7 is rounded up to 5.9 is rounded up to 17.8

16 You round up to the nearest tenth if the hundredths digit is 5,6,7,8 or 9.
4.67 is rounded up to 4.7 is rounded up to 5.9 is rounded up to 17.8 is rounded up to 125.3

17 You round up to the nearest tenth if the hundredths digit is 5,6,7,8 or 9.
4.67 is rounded up to 4.7 is rounded up to 5.9 is rounded up to 17.8 is rounded up to 125.3 is rounded up to 46.4

18 Watch out for numbers which have 9 in the tenths column.
e.g If you are rounding up, you will make 10 tenths. This makes 1 unit, so you have to round to the next whole number (in this case to 3).

19 Watch out for numbers which have 9 in the tenths column.
e.g If you are rounding up, you will make 10 tenths. This makes 1 unit, so you have to round to the next whole number (in this case to 3). For the same reason, becomes 24

20 Watch out for numbers which have 9 in the tenths column.
e.g If you are rounding up, you will make 10 tenths. This makes 1 unit, so you have to round to the next whole number (in this case to 3). For the same reason, becomes 24 becomes 13

21 Watch out for numbers which have 9 in the tenths column.
e.g If you are rounding up, you will make 10 tenths. This makes 1 unit, so you have to round to the next whole number (in this case to 3). For the same reason, becomes 24 becomes 13 And 6.98 becomes 7

22 EXAMPLE 1 Using a Number Line to Round Use a number line to round 3.87 to the nearest tenth.

23 EXAMPLE 1 Using a Number Line to Round Use a number line to round 3.87 to the nearest tenth.

24 EXAMPLE 1 Using a Number Line to Round Use a number line to round 3.87 to the nearest tenth. ANSWER

25 EXAMPLE 1 Using a Number Line to Round Use a number line to round 3.87 to the nearest tenth. ANSWER The decimal 3.87 rounds up to 3.9.

26 GUIDED PRACTICE for Example 1 Use a number line to round the decimal as specified.

27 GUIDED PRACTICE for Example 1 Use a number line to round the decimal as specified. (nearest one)

28 Use a number line to round the decimal as specified.
GUIDED PRACTICE for Example 1 Use a number line to round the decimal as specified. (nearest one)

29 Use a number line to round the decimal as specified.
GUIDED PRACTICE GUIDED PRACTICE for Example 1 Use a number line to round the decimal as specified. (nearest one) The decimal 1.3 is closer to 1 than to 3

30 Use a number line to round the decimal as specified.
GUIDED PRACTICE GUIDED PRACTICE for Example 1 Use a number line to round the decimal as specified. (nearest one) The decimal 1.3 is closer to 1 than to 3 ANSWER The decimal 1.3 rounds down to 1.

31 That’s it for now......