Addition Properties

Associative

100

(21+89) +34=(34+89)+?  What is the question mark?

? = 21

200

(45+67) +99 = (99+ 67) + ?

? = 45

300

(11+82) +90 = (90+?) + 11

? = 82

400

(33+22) +88 = (?+22) +33

? = 88

500

(66+55) + 87=(?+55)+ 66 

? = 87

Commutative

100

1,908,766+4,009,090 = ?+1,908,766

? = 1,908,766

200

56+45 = 45+?

? = 56

300

1,000,000,000+? = 1,000,000,000+1,000,000,000

? = 1,000,000,000

400

7,934,562+8,956,789 = ?+7,934,562

? = 8,956,789

500

?+567 = 567+657

? = 657

Identity

100

0+980,987=?

? = 980,987

200

?+0=45

? = 45

300

43+?= 43

? = 0

400

?+?= 78

1. ? = 78

2. ? = 0

500

1,456,678,323+0= ?

? = 1,456,678,323