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Round to Nearest 10 and 100
Copyright © 2013 Kelly Mott
FOCUS QUESTION: What does it mean to
round a number?
Copyright © 2013 Kelly Mott
When you round a number, you are replacing it with another number that tells about how much or how many.
You’re saying what the number is closest to.
Copyright © 2013 Kelly Mott
Here are some examples.
Copyright © 2013 Kelly Mott
What is 13 rounded to the nearest ten?• Find 13 on the number line. Put a dot.• Is 13 closer to 10 or 20? __________________• Answer: 13 rounded to the nearest ten is ____
10 11 12 13 14 15 16 17 18 19 20
Copyright © 2013 Kelly Mott
Round to the Nearest Ten
What is 19 rounded to the nearest ten?• Find 19 on the number line. Put a dot.• Is 19 closer to 10 or 20? __________________• Answer: 19 rounded to the nearest ten is ____
10 11 12 13 14 15 16 17 18 19 20
Copyright © 2013 Kelly Mott
Round to the Nearest Ten
Does this make sense?
Copyright © 2013 Kelly Mott
Now let’s try rounding some numbers to the nearest 10.
Copyright © 2013 Kelly Mott
Practice # 1:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
23
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 2:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
36
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 3:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
41
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 4:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
19
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 5:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
68
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 6:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
74
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 7:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
25
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 8:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
52
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Does this make sense?
Copyright © 2013 Kelly Mott
Now let’s try rounding some harder numbers to the
nearest 10.
Copyright © 2013 Kelly Mott
Practice # 1STEPS:1. Underline the place you are
rounding to.2. Write down the number(s) to
the left of the underlined digit.3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
139
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 2STEPS:1. Underline the place you are
rounding to.2. Write down the number(s) to
the left of the underlined digit.3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
653
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 3STEPS:1. Underline the place you are
rounding to.2. Write down the number(s) to
the left of the underlined digit.3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
376
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 4STEPS:1. Underline the place you are
rounding to.2. Write down the number(s) to
the left of the underlined digit.3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
521
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 5STEPS:1. Underline the place you are
rounding to.2. Write down the number(s) to
the left of the underlined digit.3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest ten:
842
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Does this make sense?
Copyright © 2013 Kelly Mott
Let’s try rounding some numbers to the nearest 100.
Copyright © 2013 Kelly Mott
Practice # 1:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest thousand:
4,833
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 2 :STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest thousand:
6,117
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 3:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest thousand:
7,438
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 4 :STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest thousand:
3,872
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 5:STEPS:1. Underline the place you are
rounding to.2. Circle the number to the right.
3. If the number to the right is 0, 1, 2, 3, or 4, then the underlined number stays the same.
4. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
5. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest thousand:
5,306
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Does this make sense?
Copyright © 2013 Kelly Mott
Now let’s try rounding some harder numbers to the
nearest 100.
Copyright © 2013 Kelly Mott
Practice # 1:STEPS:
1. Underline the place you are rounding to.
2. Write down the number(s) to the left of the underlined digit.
3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest hundred:
34,833
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 2:STEPS:
1. Underline the place you are rounding to.
2. Write down the number(s) to the left of the underlined digit.
3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest hundred:
13,285
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 3:STEPS:
1. Underline the place you are rounding to.
2. Write down the number(s) to the left of the underlined digit.
3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest hundred:
26,435
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 4:STEPS:
1. Underline the place you are rounding to.
2. Write down the number(s) to the left of the underlined digit.
3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest hundred:
78,409
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Practice # 5:STEPS:
1. Underline the place you are rounding to.
2. Write down the number(s) to the left of the underlined digit.
3. Circle the number to the right.4. If the number to the right is 0,
1, 2, 3, or 4, then the underlined number stays the same.
5. If the number to the right is 5, 6, 7, 8, or 9, then the underlined number needs to go up 1 more number.
6. Every number to the right of the underlined number becomes a zero.
Copyright © 2013 Kelly Mott
Round to the nearest hundred:
54,072
Hint for the Circled Number:4 or less just ignore.5 or more, add 1 more.
Does this make sense?
Copyright © 2013 Kelly Mott
FOCUS QUESTION: When might you use rounding in everyday
life?
Copyright © 2013 Kelly Mott
Copyright © 2013 Kelly Mott
