Question

Which property would allow you to use mental computation to simplify the problem 27 + 15 + 3 + 5?

Answer 1

commutative property of addition.

a sequence of additions can be done in any order and the total remains the same.

Explanation:

so, we can actually do

27 + 3 + 15 + 5

and now it is easy to combine 27+3 to 30 and 15+5 to 20, and to make the final calculation of 30 + 20 = 50 in our minds.