9 + 510 + 4 = 523
48 plus 510 is 558
2/9 + 4/510/45 + 36/4546/45 or 1 1/45
9 + 9 + 9 + 9 + 9 + 9 + 6 + 6 + 6 + 6 + 2 + 2 + 23 + 3 + 3 + 4 + 4 + 4 = 123
510 + 810 = 1320
9 + 4 + 4 + 4 + 4 + 4 + 5 = 34
40100 + 510 = 40610
Yes because they all add up to 18
520
30! 29
Commutativity.
3610
9 + 4 + 7 + 8 = 28