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Find the sum for: Take out your pencil, QTD sheet and H.W. (Redbook 1-1). Get started on the QTD. Is anyone absent at your table? Can you fill out an absent slip for them? 1.) 16 + 19 2.) 8,589 + 6,867 3.) 1,275 + 863 4.) 18,956 + 24,460 ANSWERS for QTD: Find the sum for: 1.) 16 + 19 Anyone have the answer for #1?: 1.) 35 2.) $8,589 + $6,867 2.) 15,456 3.) 1,275 + 863 3.) 2,138 4.) 18,956 + 24,460 4.) 43,416 Your answers are great but in a minute I am going to change the directions… Thumbs up if you got all 4 questions correct!! Today’s Goal: Estimate with whole numbers By the end of class today you will learn: To estimate with whole numbers. When to estimate and when to round. Did I overestimate or underestimate? _____________________________________ T.O. ** ANSWER THIS QUESTION** Is rounding the same or different from estimating? Explain your answer. Let’s round some numbers: RULES: Pay attention to the place value indicated. MILLIONS hundreds THOUSANDS ONES Tens ones hundreds Tens ones hundreds Tens ones 2 4, 9 4 0, 6 3 5 5 or higher, round the number to the left up one OR Less than 5, leave the number to the left the same LET’S PRACTICE: Thumbs up if you round up, OR thumbs down if you keep it the same. HINT: Mrs. Nelson, tell them what place to round to. (Look at the chart above for help) (overestimate or an underestimate?) 5,789 Work on 1-2 reteach, we’ll go over it in 2 minutes. 451 4,907 15,298 * 45,999 Reteach 1-2 Answers 1.) hundreds 789 ~ + 453 ~ 2.) Thousands 4,987 ~ - 2,348 ~ 3.) Tens 456 ~ 460 + 875 ~ +880 1,340 4.) Tens 876 ~ - 432 ~ 5.) Hundreds 6,898 ~ + 2,671~ 6.) Thousands 1,857 ~ 2,000 + 3,598 ~ + 4,000 6,000 7.) Hundreds 8,813 ~ - 2,384 ~ 8.) Thousands 9,128 ~ - 4,716 ~ 8,800 - 2,400 6,400 880 - 430 450 NEW DIRECTIONS for the QTD: 1.) Mrs. Nelson invited 12 girls and 19 boys to a party. About how many plates did she need to buy? Why is an exact answer NOT needed? HINT: Do they sell packages of 31 in the store? ROUND the number of plates needed.. 16 ~ _____ 19 ~ _____ Your answer is…? ____35___ Is this (35) an exact answer? Explain how you know. The EXACT answer is 31. Your answer of 35 is called an ESTIMATE. You rounded the number of plates to find about how many I needed, that’s called an estimate. You _______ numbers, __________ are answers. round estimates Try this with your partner Anthony has $8,589 in the bank and Jacob has $6,867 in the bank. They want to put their money together to buy a sports car. About how much money do they have? With your partner: 1.) Find the answer to the question: 2.) Should the answer you found be exactly how much they have or an estimate? Explain. 3.) What are your rounded #’s?: _____________ your estimated #’s?: ____________ How did you know what to do? or what to round to? THINK AND DISCUSS: Discuss your answer with another group. Same/Different? Exact Round to thousand s Round to hundreds Round to tens $8,589 $9,000 $8,600 $8,590 How many different answers could you have to this problem? Why that many? $6,867 $7,000 $6,900 $6,870 15,456 $16,000 $15,500 $15,460 Would one answer be MORE correct then another? Compare each answer to the exact answer, what do you notice? This is called an OVERESTIMATE. What does that mean? How is possible that they are all over the exact answer? Ticket Out: 1.) Estimate each sum by rounding to the tens place. 10,892 + 4,821= Answer is: 10,900 + 4,800= 15,700 2.) Is rounding the same or different from estimating? Use the example above to support your answer. Homework: Textbook page 12 #6-15 on a separate sheet of paper. Show your work!