Readin
Look at the two sums shaded in the addition table. Why are the sums the same?
+
0
1
2 3
4
5
because
5 x 9 = 9 x 5
0
1
2
because 9 is greater
than 5
unwN -
because
5 +9= 9+5
WNO
0 00 von A
6 7 8 9 10
3 4 5 6 7 8 9 10
2 3 4 5 6 7 8 9 10 11
3 4 5 6 7 8 9 10 11 12
4 5 6 7 8 9 10 11 12 13
5 6 7 8 9 10 11 12 13 14
6 7 8 9 10 11 12 13 14 15
6 7 8 9 10 11 12 13 14 15 16
7 8 9 10 11 12 13 14 15 16 17
9 10 11 12 13 14 15 16 17 18
because 5 and 9 are
both odd numbers
6
7
8
10 11 12 13 14 15 16 17 18 19
10 10 11 12 13 14 15 16 17 18 19 20