Addition Properties
Find the sum. Identify the addition property.
(4+3)+6=?
4+(3+6)=?
13
Associative Property
Find each sum.
256+183=?
439
Estimate. Round each addend to the indicated place value.
349+252; hundreds
600
Lennox has 3 cookies, Violet has 5, and Quinn as 7. How many cookies do they have in all?
15 cookies
Estimate. Round each addend to the indicated place value.
1,321+2,112; tens
3,400
Find the sum. Identify the addition property.
12+0=?
12; Identity Property
Find each sum.
531+142=?
673
Estimate. Round each addend to the indicated place value.
412+187; tens
600
I made $457 mowing lawns on Saturday, and $321 mowing lawns on Sunday. Is it reasonable to say I made about $800 mowing lawns this weekend? Why or why not?
Yes, because $457+$321 is $778 which rounds to $800
Estimate. Round each addend to the indicated place value.
2,210+3,211; hundreds
5,400
Find the missing number. Identify the addition property.
13+14=?+13
14
Communicative Property
Find each sum.
2,367+6,930=?
9,297
Estimate. Round each addend to the indicated place value.
284+146; hundreds
400
I rode my bike for 16 miles on Monday, 12 miles on Tuesday, and 23 miles on Wednesday. About how many miles did I ride in all?
About 50 miles
Estimate. Round each addend to the indicated place value.
4,191+1,710; tens
5,900
Find the sum. Identify the addition property.
1,213+0=?
1,213
Identity Property
Find each sum.
3,957+1,947= ?
5,904
Estimate. Round each addend to the indicated place value.
509+399; tens
900
I make $300 every month. If I save $63 last month and $104 this month, how much money will I have saved in all?
$167
Estimate. Round each addend to the indicated place value.
3,380+2,439; hundreds
5,800
Find the sum. Identify the addition property.
343+ (7+12)=?
(343+7)+12=?
BONUS: Which grouping (the first or the second) makes the most sense mathematically?
362
Associative Property
The second, because 342 and 7 makes an easy number that is easy to add in your head.
Find each sum.
5,383+3,783=?
9,166
Estimate. Round each addend to the indicated place value.
772+334; hundreds
1,100
I have 3 pet cats. Each cat has 5 toys, 2 food bowls, and 1 litter box. How many items are needed for all the cats?
24 items
Estimate. Round each addend to the indicated place value.
7,391+8,239; tens
15,600