Answer: A. 30+(-12)+70
Step-by-step explanation:
Commutative property of addition is given by : a+b = b+a , where a and b can be any expression of real numbers.
It basically changes the order of the so that simplification of any expression becomes easier.
In A. we use this property as
30+(-12)+70 = 30+[(-12)+70]
= 30 + [70+(-12)] [we switched order of (-12) and 17]
= 30+70-12
= 100-12
= 88
The rest of the expression already arranged accordingly, there is no need to apply commutative property to change the order of the numbers.
So the correct option is A. 30+(-12)+70.
