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Whole Numbers and Their Operations. Third Grade CRCT Prep. What are whole numbers?. The digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 are used to write whole numbers. Whole numbers can be expressed in standard notation or expanded notation Standard- 3,421 Expanded- 3,000 + 400 + 20 + 1
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Whole Numbers and Their Operations Third Grade CRCT Prep
What are whole numbers? • The digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 are used to write whole numbers. • Whole numbers can be expressed in standard notation or expanded notation • Standard- 3,421 • Expanded- 3,000 + 400 + 20 + 1 • Numbers may also be expressed in words (Three thousand, four hundred twenty-one • Models can also express numbers (place value blocks)
Answer the following: This is a model representation of which number?
Answer the following: • 80,000 + 2,000 + 500 + 30 + 2 is the expanded notation of which number? • 700,000 + 300 + 4 is the expanded notation of which number? • Which of the following is in standard notation? • A. 3,000 + 20 + 1 • B. Three thousand, twenty-one • C. 3,021 • D. (3 x 1,000) + (2 x 10) + 1
Place Value 867, 921
Try this question: • What is the place value for the underlined digit in 87,457? • A. hundreds • B. thousands • C. ten thousands • D. hundred thousands • HINT: USE THE CHART
Try This Question: • By how much would the value of 5,647 be decreased if the 5 were replaced by a 2? • A. 3 • B. 30 • C. 300 • D. 3,000 • HINT: WRITE THE NUMBER 5,647. ERASE THE 5 AND WRITE A 2 IN ITS PLACE. HOW MUCH SMALLER IS IT. DECREASED MEANS SMALLER!!!
Comparing and Ordering • Symbols: • > means greater than • < means less than • = means equal to • 56>7 (56 is greater than 7) • 9<90 (9 is less than 90)
Words to watch: • Increased: means bigger • Decreased: gets smaller • Greatest to least: biggest to smallest • Least to greatest: smallest to biggest
Answer the following: • Put the following numbers in order from greatest to least: • A. 890 • B. 89 • C. 8,900 • D. 89,000 • HINT: IT’S ASKING FROM BIGGEST TO SMALLEST!!!
Answer the Following: • Put the following numbers in order from least to greatest: • A. 7,654 • B. 7,987 • C. 7,897 • D. 7,777 • HINT: SMALLEST TO LARGEST!!! LINE UP THE NUMBERS AND LOOK AT EACH PLACE VALUE.
Operations for Whole Numbers Words to watch: ADDITION: Altogether; How many in all; Total; Sum SUBTRACTION: How much greater? What is the difference? How much left? How many more?
More words to watch • MULTIPLICATION: • How many? • Product • DIVISION: • How many? • Quotient
Watch For Estimates!!! • If it says about, or best estimate: • You must estimate!!! • You do this by rounding!!! • 678 + 901 • I round 678 to 700 and 901 to 900. The estimated sum is 1,600!!!
Solve: • Don was selling cans of peanuts for a school project. He sold 23 on Monday, 78 on Wednesday, and 47 on Thursday. About how many cans of peanuts did Don sell?A. 100 B. 150 C. 250 D. 300 • HINT: WHICH OPERATION??
Solve: • Professional golfers often hit golf balls as far as 320 yards. Major league baseball players hit home runs as far as 450 feet. What is the difference between these distances? • A. 130 yards B. 170 yards C. 130 feet D. 170 feet • HINT: WHAT OPERATION???
Solve: • It is 71 miles from Boston, MA, to Concord, NH. It is 138 miles from Concord, NH, to Colebrook, NH. About how many miles is this altogether?A. 100 B. 200 C. 300 D. 400 • WHAT OPERATION?
Solve • Cedar Grove Elementary School is having a jump-rope contest. Wilson jumped 293 times. Cathy jumped 412 times. Which is the BEST ESTIMATE of how many more times Cathy jumped than Wilson?A. 100 B. 200 C. 300 D. 400 • WHAT OPERATION???
Solve: • A bay is 12 fathoms deep. A fathom is equal to 6 feet. How many feet deep is the bay?A. 2 feet B. 18 feet C. 72 feet D. 96 feet • HINT: BIGGER OR SMALLER??? WHAT MAKES SENSE???
Solve: • Mrs. Wall bought eight books of stamps. If each book contains 18 stamps, how many stamps did she buy?A. 10 B. 26 C. 84 D. 144 • BIGGER OR SMALLER?? WHAT OPERATION???
Solve: • Jan has 40 bags of marbles. There are 70 marbles in each bag. How many marbles does Jan have?A. 110 B. 280 C. 1110 D. 2800
Solve • The 21 students will be divided up into groups. Each of the 7 adults will have the same number of students in a group. How many students will be in each group?A.2 B. 3 C. 4 D. 5 • BIGGER OR SMALLER???? WHAT OPERATION???
Solve: • Darion visited his friends who live near a beach. He brought back shells to give to the children in his class. He had 125 shells and gave 5 shells to each child. What should you do to find out how many children received shells from Darion?A. add B. subtract C. multiply D. divide
Inverses or Opposites!!! • You can use an inverse to check your work!!! • The inverse of addition is subtraction • 67 + 33 = 100 • 100 – 33 = 67 • You can use subtraction to check addition • You can use addition to check subtraction • The inverse of multiplication is Division • You can use multiplication to check division • You can use division to check multiplication • 8 x 9 = 72 • 72 / 9 = 8
Solve • Which number sentence is related to 800 – 600 = 200? • A. 600 + 400 = 1000 • B. 200 + 800 = 1000 • C. 200 + 600 = 800 • D. 800 – 200 = 600
Multi-Step Problems • Try working backwards!!! • Cherie has a rock collection. She gave 6 rocks to Tommy for his birthday. She traded 3 rocks to Sally for marbles. Cherie now has 15 rocks left. How many did she start with?A. 6 B. 9 C. 15 D. 24 • Try starting with 15 and adding the other rocks!!!
Important and Not??? • In one weekend, a class of 30 students read a total of 1,000 pages. If 10 students read a total of 379 pages, how many pages did the other 20 students read?A. 621 B. 731 C. 1,621 D. 1,731 • What is the operation?? Which numbers are important?? Some of these are not!!!
Draw a picture!!!! • You are eighth in line to swing at the playground. If every person ahead of you swings for 5 minutes, how long will you wait to swing?A. 5 minutes B. 13 minutes C. 35 minutes D. 40 minutes
Work Backwards • The Costume Store sold half of its supply of costumes on Friday. Eight more were sold on Saturday. Then there were only 18 left in the store. How many costumes were in the store when it opened on Friday?A. 52 B. 26 C. 20 D. 13 • Start with 18 and add. What does half mean??? Divide by 2.