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How to Round Whole Numbers. A Number Line. When rounding number, some times it helps to remember and to use a number line. | | | | | | | | | | |
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A Number Line When rounding number, some times it helps to remember and to use a number line. | | | | | | | | | | | 0 10 20 30 40 50 60 70 80 90 100 | | | | | | | | | | 100 200 300 400 500 600 700 800 900 1000 | | | 1 000 000 2 000 000 3 000 000
Rounding Numbers • BASIC RULES • If the number to the RIGHT of the Rounding Number is 5 or more (5, 6, 7 8 or 9) then the LEFT (Rounding Number) number goes UP by ONE place. • 2. If the number to the RIGHT of the Rounding Number is 4 or less (4, 3, 2, 1 or 0) then the LEFT (Rounding Number) number remains the SAME. • 3. Every number AFTER the Rounding Number becomes 0. • 4. Everything BEFORE the Rounding Number remains the same. • 5. If the Rounding Number is a 9 and it goes up by one, then a 0 is placed in the Rounding Number Place and 1 is moved to the next place to the LEFT. (same as carrying in adding)
How to Round Whole Numbers to the Tens Place Example: Round 78 to the nearest tens place | | | | | | | | | | 80 78 70 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the tens place 78
How to Round Whole Numbers to the Tens Place Example: Round 78 to the nearest tens place 2. Look to the right of the place you want to round to, Now look to the right of the 78 tens place Look here • If the digit is 5, 6, 7, 8 or 9 – the digit in the tens place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the tens place STAYS THE SAME The 7 in the tens place 78 80 goes up by 1 to 8
How to Round Whole Numbers to the Tens Place Example: Round 78 to the nearest tens place 3. Next, the digits to the right of the rounding place become zero. Now the 8 becomes zero 78 becomes 80 4. Anything to the left of the rounding place remains the same. So 78 rounded to the nearest tens place is 80
How to Round Whole Numbers to the Tens Place Example: Round 123 to the nearest tens place | | | | | | | | | | 130 120 123 To Round: 123 Here is the tens place Look to the right 3, so the 2 in the tens place stays the same. On the left On the left hand side, all stays the same 123 rounds to 120
How to Round Whole Numbers to the Tens Place Example: Round 1 099 to the nearest tens place | | | | | | | | | | 1100 1090 1099 To Round: 1099 Here is the tens place with 9 to its right The 9 in the tens place goes up by one. **But, 9 goes to 10 and we only have one place 1100 So we need to move over one more place to the left adding 1 to the hundreds place and 0 to the tens place. All on right changes to zero. 1 099 rounds to 1 100
How to Round Whole Numbers to the Tens Place Example: Round the following to the nearest tens place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 __2 65 234 2 343 45 678 65 723 199 789 1 222 222 0 70 230 2 340 45 680 65 720 199 790 1 222 220 Look to the value of the place to the right of the tens place
Practice Round the following numbers to the nearest tens place. 45 67 123 456 890 1232 a) 50 b) 70 c) 120 d) 460 e) 890 f) 1 230
How to Round Whole Numbers to the Hundreds Place Example: Round 145 to the nearest hundreds place | | | | | | | | | | 200 100 145 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the hundreds place 145
How to Round Whole Numbers to the Hundreds Place Example: Round 145 to the nearest hundreds place 2. Look to the right of the place you want to round to, Now look to the right of the 145 tens place • If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the hundredsplace STAYS THE SAME The 1 in the hundreds place 145 100 stays the same
How to Round Whole Numbers to the Hundreds Place Example: Round 145 to the nearest hundreds place 3. Next, the digits to the right of the rounding place become zero. Now the 4 and 5 becomes zero 145 becomes 100 4. Anything to the left of the rounding place remains the same. So 145 rounded to the nearest hundreds place is 100
How to Round Whole Numbers to the Hundreds Place Example: Round the following to the nearest hundreds place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 _ _ 2 _65 234 2 343 45 678 65 723 199 789 1 222 222 0 100 200 2 300 45 700 65 700 199 800 1 222 200 Look to the value of the place to the right of the hundreds place
Practice Round the following numbers to the nearest hundreds place. 49 136 293 456 1 890 12 345 a) 0 b) 100 c) 300 d) 500 e) 1 900 f) 12 300
How to Round Whole Numbers to the Thousands Place Example: Round 9 871 to the nearest thousands place | | | | | | | | | | | 10 000 9000 9 871 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the thousands 9 871
How to Round Whole Numbers to the Thousands Place Example: Round 9 871 to the nearest thousands place 2. Look to the right of the place you want to round to, Now look to the right of the 9871 thousands place • If the digit is 5, 6, 7, 8 or 9 – the digit in the thousands place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the thousands place STAYS THE SAME The 9 in the thousands place 9871 10 000 goes up by 1
How to Round Whole Numbers to the Thousands Place Example: Round 9 871 to the nearest thousands place 3. Next, the digits to the right of the rounding place become zero. Now the 8,7 and 1 becomes zero 9871 becomes 10 000 4. Anything to the left of the rounding place remains the same. So 9 871 rounded to the nearest thousand place is 10 000
How to Round Whole Numbers to the Thousands Place Example: Round the following to the nearest thousands place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 _ _ _ 2 _ _65 _234 2 343 45 678 65 723 199 789 1 222 222 0 0 0 2 000 46 000 66 000 200 000 1 222 000 Look to the value of the place to the right of the thousands place
Practice Round the following numbers to the nearest thousands place. 1 234 78 902 12 666 9 987 2 890 1 234 512 a) 1 000 b) 79 000 c) 13 000 d) 10 000 e) 3 000 f) 1 235 000
How to Round Whole Numbers to the Ten Thousands Place Example: Round 19 012 to the nearest ten thousands place | | | | | | | | | | 20 000 19 000 19 012 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the ten thousands place 19 012
How to Round Whole Numbers to the Ten Thousands Place Example: Round 19 012 to the nearest ten thousands place 2. Look to the right of the place you want to round to, Now look to the right of the 19 012 ten thousands place • If the digit is 5, 6, 7, 8 or 9 – the digit in the ten thousands place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the ten thousandsplace STAYS THE SAME The 1 in the ten thousands place 19 012 20 000 goes up by one
How to Round Whole Numbers to the Ten Thousands Place Example: Round 19 012 to the nearest ten thousands place 3. Next, the digits to the right of the rounding place become zero. All the numbers on the 19 012 becomes 20 000 right becomes zero 4. Anything to the left of the rounding place remains the same. So 19 012 rounded to the nearest ten thousands place is 20 000
How to Round Whole Numbers to the Ten Thousands Place Example: Round the following to the nearest ten thousands place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 _ _ 2 _65 234 2 343 45 678 65 723 199 789 1 222 222 0 70 230 2 340 45 680 65 720 199 790 1 222 220 Look to the value of the place to the right of the tens place
Practice Round the following numbers to the nearest ten thousands place. 45 653 567 809 12 342 565 456 789 112 343 a) 50 000 b) 570 000 c) 12 340 000 d) 460 000 e) 110 000
How to Round Whole Numbers to the Hundred Thousands Place Example: Round 145 to the nearest hundreds place | | | | | | | | | | 200 100 145 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the hundreds place 145
How to Round Whole Numbers to the Hundred Thousands Place Example: Round 145 to the nearest hundreds place 2. Look to the right of the place you want to round to, Now look to the right of the 145 tens place • If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the hundredsplace STAYS THE SAME The 1 in the hundreds place 145 100 stays the same
How to Round Whole Numbers to the Hundred Thousands Place Example: Round 145 to the nearest hundreds place 3. Next, the digits to the right of the rounding place become zero. Now the 4 and 5 becomes zero 145 becomes 100 4. Anything to the left of the rounding place remains the same. So 145 rounded to the nearest hundreds place is 100
How to Round Whole Numbers to the Hundred Thousands Place Example: Round the following to the nearest hundred thousands place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 _ _ 2 _65 234 2 343 45 678 65 723 199 789 1 222 222 0 70 230 2 340 45 680 65 720 199 790 1 222 220 Look to the value of the place to the right of the tens place
Practice Round the following numbers to the nearest hundred thousands place. 455 555 156 789 12 345 876 12 000 542 334 334 a) 500 000 b) 200 000 c) 12 300 000 d) 12 000 000 e) 300 000
How to Round Whole Numbers to the Millions Place Example: Round 145 to the nearest hundreds place | | | | | | | | | | 200 100 145 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the hundreds place 145
How to Round Whole Numbers to the Millions Place Example: Round 145 to the nearest hundreds place 2. Look to the right of the place you want to round to, Now look to the right of the 145 tens place • If the digit is 5, 6, 7, 8 or 9 – the digit in the hundreds place goes UP by 1 • If the digit is 0, 1, 2, 3 or 4 – the digit in the hundredsplace STAYS THE SAME The 1 in the hundreds place 145 100 stays the same
How to Round Whole Numbers to the Millions Place Example: Round 145 to the nearest hundreds place 3. Next, the digits to the right of the rounding place become zero. Now the 4 and 5 becomes zero 145 becomes 100 4. Anything to the left of the rounding place remains the same. So 145 rounded to the nearest hundreds place is 100
How to Round Whole Numbers to the Millions Place Example: Round the following to the nearest millions place To Round: 2 65 234 2 343 45 678 65 723 199 789 1 222 222 _ _ 2 _65 234 2 343 45 678 65 723 199 789 1 222 222 0 70 230 2 340 45 680 65 720 199 790 1 222 220 Look to the value of the place to the right of the tens place
Practice Round the following numbers to the nearest millions place. 1 455 555 34 156 789 999 999 13 567 789 27 800 000 a) 1 000 000 b) 34 000 000 c) 1 000 000 d) 14 000 000 e) 28 000 000
How to Round Whole Numbers Example: Round 78 to the nearest tens place | | | | | | | | | | | | 80 78 70 Use a number line to help you visualize 1. Underline the place you want to round to. Here we want the tens place 78
Some Examples: 1. Round to the nearest 10 12 ____________ Or use a number line is 12 closer to 10 or to 20?