Carry plus digits, add single digits, add ten digits to one to ten digits, add ten digits, and add the obtained number to a ten to get the result. Ma Bao can explain this to her baby. This is a simple math problem.
Extended data:
Additive commutative law
a+b=b+a
For example: 8+1=1+8 = 9100+2 = 2+100 =102.
associative law of addition
a+b+c=a+(b+c)
Example: 7+4+1= 7+(4+1) = (7+4)+1=1210-5+2 = (10)
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