Rounding
Estimate by rounding to the nearest hundred: 489- 207
500- 200= 300
9,834 + 2,958=
12,592
Ella has 36 smiley face stickers, 82 One Directions stickers, and 27 Katy Perry stickers. How many stickers does Ella have in her collection?
145 stickers
Subtract: 973-862
111
What does the Commutative property of Addition tell us? Give an example.
The Commutative Property of Addition tells us that you can change the order of the addends and the sum will remain the same. For example, 5+6=11 is the same as 6+5=11. Although the order of the addends changed, it did not effect the sum.
Estimate by rounding to the nearest hundred: 949- 651
900- 700= 200
4,673 + 262
4,953
Katy has 1,565 stamps in her collection. She gave 1,272 to the museum. How many stamps does she have now? Check your work.
293 stamps
Carrie makes 2 gifts in the time it takes Sam to make 4 gifts. When Sam has made 12 gifts, how many gifts has Carrie made?
Answers may vary
Kayla estimated 8,226+3,455 by rounding to the nearest thousand. What numbers did she add?
8,000+3,000
4,334 + 4,949 + +892=
10,175
At the Barnes and Noble, 564 cars can park. Next door, at JC Penney's 1,052 cars can park. How many parking spaces are there in all?
1,616 cars
Thomas had $3,500 in his savings account. He took out $246 to buy a new TV. How much money does he have left in his savings?
$3,254
Will the difference between 5,602 and 4,932 be greater than or less than 1,000? How do you know?
I rounded 5,602 to 5,600 and 4,932 to 4,900 and the estimated difference I got was only 700. I can use my estimated guess to tell me that my answer is going to be less than 1,000.
World War II started in 1935. The war in Afghanistan began in 2001. ABOUT how many years later did the war in Afghanistan start?
2000-1940= about 60 years
37,987 + 2096 + 15,098 + 7,947
63,128
Joey's Pizzeria made 25,567 pizzas this year. Last year they made 17,704 pizzas. How many pizzas has the pizzeria made all together? Check your work.
43,271 pizzas
Kelsey read a book with 106 pages on Wednesday, a 205 page book on Thursday, and 25 pages of a book on Friday. How many pages did she read in all? Draw a picture to show the answer.
Answers may vary.
Paula adds 65,306 and 12,206. Is her answer going to be greater or less than 80,000? How do you know?
I rounded 65,306 to 65,000 and 12,206 to 12,000 and then added the numbers together. My estimated answer was 77,000, which is less than 80,000, so I know that my exact answer is going to be less than 80,000.
The Thomas family drove 1,562 miles to Chicago, IL and then drove 790 miles to New York City, NY. About how many miles did they drive in all?
1,560 +790= about 2,350 miles
8,738+ 836 +257 +5,236 +=
15,057
Jessica had 3 pieces of fabric to sew together. One was 54 inches long, one was 67 inches long and one was 143 inches long. How long will the fabric be when she sews it all together?
54+67+143= 264 inches long
Jake wants to raise $450 for a fundraiser. He has raised $226 so far. How much does he still need to raise? Draw a picture.
Answers will vary
If we know that 76+14+32= 122, what do we know about the sum of 14+32+76? Which property helps us figure it out?
If 76+14+32= 122, we know that 14+32+76=122 also. The Commutative Property of Addition tells us that it does not matter if we change the order of the addends. Our sum will still be the same.