Question

13. Add the following using number line.
a) 5 + 7 = 7 + 5
b) (9 +2)+7 = 9+ (2+7)​

Answer 1

Answer:

1.          #2     #1 or

           #1     #2           = 12

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

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2.  (9+2 = 11) + 7 = 18 = (2 + 7) = 27