Word Problems
12 + (3 + 2) = 12 + (2 + 3)
Commutative Property
The property that states that when the grouping of addends is changed, the sum is the same.
Associative Property of Addition
Estimate using compatible numbers
172+32
Possible Estimate 175+25=200
8+3 = even sum
false, 11 is odd
349+508
857
(9+3) = (3+9)
Commutative Property
The property that states you can add two or more numbers in any order and get the same sum.
Commutative Property of Addition
Estimate 123+489 using rounding to the nearest hundred
100+500=600
23+4=even sum
false, 27 is odd
349-246
103
(2 + 3) + 1 = (1 + 3) + 2
Associative Property
Numbers that are easy to compute mentally
Compatible Numbers
Estimate by rounding to the nearest hundred
227+128
227---200
+128---100
--------------
300
sum of 147+3 is even
true, 150 is even
(246+418)-349
315
1 + 0 = 0
Identity Property of Addition
A number that is close to the exact amount
Estimate by rounding to the nearest thousand
1,284+156
1,000+0=1,000
489 rounds to 500 when rounded to the nearest hundred
true
645-236
409
(5+9) + 3 = (9+5) +3
Commutative Property of Addition
The property that says the sum of zero and a number is that number
Identity Property of Addition
Estimate by using compatible numbers
486+48
Possible Estimate
500+50=550
789 rounds to 1,000 when rounded to the nearest thousand
true
500-99
401