How can you adjust the quotient if your estimate is too high or too low? Divide Estimate = 7. Try 7 ones )

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1 ? Name 2.7 Essential Question Adjust Quotients How can you adjust the quotient if your estimate is too high or too low? Number and Operations 5.3.C Also 5.3.A MATHEMATICAL PROCESSES 5.1.D Connect When you estimate to decide where to place the first digit, you can also try using the first digit of your estimate to find the first digit of your quotient. Sometimes an estimate is too low or too high. Divide. 3, Estimate. 3, = 60 Try 6 tens. If an estimate is too low, the difference will be greater than the divisor. Divide Estimate = 7 Try 7 ones. If an estimate is too high, the product with the first digit will be too large and cannot be subtracted ) 3, Since the estimate is too low, adjust by increasing the number in the quotient ) Since the estimate is too high, adjust by decreasing the number in the quotient. Unlock the Problem A new music group makes 6,127 copies of its first CD. The group sells 75 copies of the CD at each of its shows. How many shows does it take the group to sell all of the CDs? Divide. 6, Estimate. 6, = 90 STEP 1 Use the estimate, 90. Try 9 tens. Is the estimate too high, too low, or correct? 75 ) 6,127 Adjust the number in the quotient if needed. STEP 2 Estimate the next digit in the quotient. Divide the ones. Estimate: = 2. Try 2 ones. Is the estimate too high, too low, or correct? Adjust the number in the quotient if needed. So, it takes the group _ shows to sell all of the CDs. Module 2 91

2 Try This! When the difference is equal to or greater than the divisor, the estimate is too low. Divide Estimate = 6 Use the estimate. Try 6 ones ) 336 Since, the estimate is = _ Adjust the estimated digit in the quotient if needed. Then divide. Try. Math Talk Mathematical Processes Explain why using the closest estimate could be useful in solving a division problem. Share and Show Adjust the estimated digit in the quotient, if needed. Then divide ) 1, ) ) 2,831 Problem Solving Algebra Write the unknown number for each = , = = 33 = = = 7. How do you know whether an estimated quotient is too low or too high? Explain. 92

3 Name Unlock the Problem 8. Multi-Step A banquet hall serves 2,394 pounds of turkey during a 3-week period. If the same amount is served each day, how many pounds of turkey does the banquet hall serve each day? A 50,274 pounds C 342 pounds B 798 pounds D 114 pounds a. What do you need to find? b. What information are you given? c. What other information will you use? e. Divide to solve the problem. d. Find how many days there are in 3 weeks. There are _ days in 3 weeks. f. Fill in the bubble for the correct answer choice. 9. Multi-Step Kainoa collects trading cards. He has 1,025 baseball cards, 713 basketball cards, and 836 football cards. He wants to put all of them in albums. Each page in the album holds 18 cards. How many pages will he need to hold all of his cards? 10. The Box of Sox company packs 12 pairs of socks in a box. How many boxes will the company need to pack 1,020 pairs of socks? Module 2 Lesson 7 93

4 Daily Assessment Task Mathematical Processes Fill in the bubble completely to show your answer. 11. Apply A ranch director would like to place a fence around some land he purchased for horses. He needs 992 feet of wire to fence the area. There are 45 feet of fence in each roll. How many rolls should he buy? A 25 rolls C 23 rolls B 22 rolls D 20 rolls 12. Sarah works part time at a zoo. She purchases food for the lions. The lions eat 1,330 pounds of food a year. The food comes in 22-pound bags. Which shows the closest estimate of how many bags of food Sarah orders each year? A 1, = 50 C 1, = 40 B 1, = 65 D 1, = Multi-Step Dylan traveled through Texas for the summer. He took 15 photos each day for 18 days. He placed the photos in a 30-page album. If each page has the same number of photos, how many photos are on each page? A 8 B 12 C 9 D 15 TEXAS Test Prep 14. Marcos mixes 624 ounces of lemonade. He wants to fill the 52 cups he has with equal amounts of lemonade. How much lemonade should he put in each cup? A 10 ounces 94 B C D 12 ounces 14 ounces 13 ounces

5 Homework and Practice Name Number and Operations 5.3.C Also 5.3.A MATHEMATICAL PROCESSES 5.1.D 2.7 Adjust Quotients Divide. 1. 3, , , , , , Write the unknown number for each = = 9. 3,360 =80 = _ = _ = _ Problem Solving 10. Kirsten wants to divide She estimates that 2 is the first digit in the quotient. Is her estimate correct? Explain. 11. Ming has 4,173 songs on his MP3 player. He organizes the songs into 39 playlists with the same number of songs in each list. How many songs are in each playlist? Module 2 Lesson 7 95

6 Lesson Check TEXAS Test Prep Fill in the bubble completely to show your answer. 12. Mr. Longo bakes 573 muffins to be sold at the school football game. He puts the muffins into boxes of 15. What is the greatest number of full boxes Mr. Longo will bring to the game? A 35 B 38 C 41 D Multi-Step A movie theater sold 4,494 tickets during a two-week period. If the same number of tickets were sold each day, how many tickets were sold on Wednesday and Thursday of one week? A 600 B 642 C 321 D Jenny wants to estimate the quotient for 6, Which is the best estimate for the first digit in the quotient? A 1 B 2 C 4 D An art museum has 1,120 paintings. To display the paintings, the curator will divide the paintings equally among 16 rooms. How many paintings will be displayed in each room? A 68 B 71 C 70 D Factory workers pack 25 umbrellas in each box. If 1,300 umbrellas are shipped out, how many boxes were packed? A 52 B 45 C Multi-Step A store had 1,116 customers on Monday, 882 customers on Tuesday, and 1,194 customers on Wednesday. The store is open 14 hours each day. If the same number of customers arrived each hour during the three days, how many customers arrived each hour? A D 40 B 47 C 76 D 70