Vocabulary
Name that property: 17+14=14+17
Commutative Property
Which number would make the equation true?
12 + __ = 15 + 12
15
What is 421 rounded to the nearest ten?
420
Sara collected 345 seashells and her brother collected 127 seashells. How many more seashells did Sara collect than her brother?
218 more seashells
Name that property:65+0=65
Identity Property
Which number would make the equation true?
3 + ( 7 + 8 ) = (3 + __ ) + 8
7
What is 268 rounded to the nearest ten?
270
Sara collected 345 seashells and her brother collected 127 seashells. How many seashells did they collect in all?
472 seashells
Name that property:8 +( 5+ 9)= (8 + 5 )+ 9
Associative Property
Which number would make the equation true?
30 + __ = 30
0
What is 122 rounded to the nearest hundred?
100
Michelle collected 291 stickers last month. Today she collected 85 stickers and yesterday she collected 77 stickers. How many stickers does she have now?
453 stickers
To check your answer to an addition equation you can use subtraction because it is the ___________ operation.
Inverse
Which number would make the equation true?
193 + ( 27 + 82 ) = (___ + 27 ) + 82
193
What is 759 rounded to the nearest hundred?
800
Elena has $265. She buys a jacket that costs $107 and a sweater that costs $69. How much money does she have left?
$89
You are __________ when you use the nearest multiple of ten or hundred.
Rounding or Estimating
Which number would make the equation true?
262 + 179 = ____ + 262
179
Maria said 91 rounds to 100. Did she round to the nearest ten or hundred?
Hundred
John read 211 pages of his book today and 175 pages yesterday. About how many pages has he read?
400 pages OR 390 pages