Question

Here is an addition sentence.

Answer 1

Answer: B. $3+(1+11)=15$

Step-by-step explanation:

1. By definition, the associative property of addition is:

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

2. Therefore, if you have the following expression:

$(3+1)+11=15$

You apply  the Asociative property of addition by regrouping the numbers as following:

$3+(1+11)=15$

3. Then, you can conclude that the correct option is B.