2.7 - 20 + 39 = 21.7
39 + 39 + 39 + 39 + 39 + 39 = 234
15
59
273
61
Something's missing from your question. There are 20 answers to your question. 39 + 0 = 39 38 + 1 = 39 37 + 2 = 39 . . . 19 + 20 = 39
5
The commutative property of addition.
-21.
90
90
75+2(32)+4(39)+47 =75+64+156+47 =75+220+47 =122+220 =342