Answers

2014-08-04T19:46:01+08:00
1) 17+42+3 = 62 (Addition Property)
2) (12x7)+(13x12) (Multiplication Property)
  =84+156 = 240 (Addition Property)
3) (78x1) (Identity Property of Multiplication) + (99x78)
  =78+7722 = 7800 (Addition Property)

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