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Math – Review & Practice. Place Value. What are digits?. Digits are the numbers…. 8. 4. 5. 1. 6. 7. 3. 9. 2. 0. Together, they can be combined to make up all of the numbers. What is place value?. Place value is the value given to the place a digit has in a number.
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Math – Review & Practice Place Value
What are digits? • Digits are the numbers… 8 4 5 1 6 7 3 9 2 0 Together, they can be combined to make up all of the numbers.
What is place value? • Place value is the value given to the place a digit has in a number. For example: Look at the number 3,056. The 5 is in the ten’s place, so it’s value equals 50. You try! Look at the number 14,289. What is the value of the underlined digit? The 4 is in the thousands place, so the value is 4,000.
What is the value of the underlined digit? 1. 14,768 700 1 2. 256,201 3. 134,783 30,000 5,000 4. 845,682 600,000 5. 614,503 6. 1,234,568,245 200,000,000
What is a period in math? • A period is a group of three digits in a number, separated by a comma. Hundred Ten Thousands Hundreds Thousands Thousands Tens Ones , Thousands Period Ones Period Comma
Get a pencil and write the numbers below in standard form. Two hundred four million, one hundred one 204,000,101 40,000,000 + 30,000 + 200 + 8 40,030,208
Write the numbers below in expanded form. 1. One thousand, two hundred twenty-five 1,000 + 200 + 20 + 5 2. 543,031 500,000 + 40,000 + 3,000 + 30 + 1 3. Fifty billion, two hundred eight 50,000,000,000 + 200 + 8
Write the word name for the numbers below. • 25,658,012,041 Twenty-fivebillion,six hundred fifty-eight million,twelvethousand,forty-one • 237,984.02 Two hundred thirty-seventhousand,nine hundred eighty-four andtwo hundredths
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 5 hundred thousands in 500,000.
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 50 ten thousands in 500,000.
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 500 thousands in 500,000.
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 5,000 hundreds in 500,000.
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 50,000 tens in 500,000.
Place Value Relationships Hund Thous. Ten Thous Thousand Hundred Tens Ones 5 0 0 0 0 0 There are 500,000 ones in 500,000.
Comparing Numbers What does it mean to compare? You are deciding which of 2 numbers is greater. Example: Compare 28,462 and 2,846 Step 1: Check to see if there are the same number of digits. Step 2: If not, the number with more digits has a greater value. 2 8, 4 6 2 The first number has 5 digits. The second number has 4 digits. 2, 8 4 6 5 digits > 4 digits So, 28,462 > 2,846 Or, 2,846 < 28,462
Comparing Numbers What does it mean to compare? You are deciding which of 2 numbers is greater. Example: Compare 8,193 and 8,186 Step 1: Begin at the left if there are the same number of digits. Compare. Step 2: Find the 1st place the digits differ. Compare. 8, 3 1 9 Both numbers have an 8 in the thousands place. Both numbers have a 1 in the hundreds place. 8, 1 8 6 9 tens > 8 tens So, 8,193 > 8,186 Or, 8,186 < 8,193
You try it! Compare. 1. 456 465 2. 54,193 54,183 3. 125 152 4. 167,465 167,465 < > < =
Ordering Numbers What does it mean to order numbers? You are placing the numbers from least to greatestorgreatest to least. Example: Order from least to greatest. 3,516; 3,432; 3,540; 3,435 3,432; 3,435; 3,516; 3,540 Order the same numbers from greatest to least. 3,540; 3,516; 3,435; 3,432
Exploring Rounding 1. What does estimatemean? It means to find a number close to the exact number. 2. What does roundingmean? It means replacing a number with a number that tells abouthow many or how much.(Rounding is a way to estimate.)
Round 56 to the nearest ten. 56 10, 20, 30, 40, 50, 60, 70, 80, 90, When I count bytens, 56 is between 50 and 60. So, my answer is either 50 or 60. 56 is closer to 60, so my answer is 60. 60 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
Round 35 to the nearest ten. 35 10, 20, 30, 40, 50, 60, 70, 80, 90, When I count bytens, 35 is between 30 and 40. So, my answer is either 30 or 40. 35 is halfway to 40, so my answer is 40. 40 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
Round 517 to the nearest hundred. 517 100, 200, 300, 400, 500, 600, 700, 800, 900, When I count byhundreds, 517 is between 500 and 600. So, my answer is either 500 or 600. 517 is closer to 500, so my answer is 500. 500, 510, 520, 530, 549, 550, 560, 570, 580, 590, 600
Round 968 to the nearest hundred. 968 100, 200, 300, 400, 500, 600, 700, 800, 900, 1,000 When I count byhundreds, 968 is between 900 and 1,000. So, my answer is either 900 or 1,000. 968 is closer to 1,000, so my answer is 1,000. 900, 910, 920, 930, 949, 950, 960, 970, 980, 990, 1,000