Question

Select the number property that will justify the step in the following expression. 6 + (14 + 70) = (6 + 14) + 70 = 20 + 70 = 90

Answer 1

1. Commutative property        L

Answer 2

Answer: Associative property of addition.

Step-by-step explanation:

The rule for the Associative property of addition is:

$a + (b + c) = (a + b) + c$

Therefore, this property establishes that it does not matter how you group the numbers, the sum will not change.

You can observe that, in this case, the numbers of the given addition can be grouped as $6 + (14 + 70)$ or $(6 + 14) + 70$, and the sum will be the same.

Then, you get:

$6 + (14 + 70) = (6 + 14) + 70 = 20 + 70 = 90$