Pascal M. answered • 09/13/15
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In a problem like this you always start with the multiplications (divisions). Then you do the additions (subtractions). The only time you would compute an addition before a multiplication would be if the addition is inside a set of parentheses (not the case here).
30-5*4+2
30-20+2
Now, just compute from left to right
30-20+2
10 + 2
=12
You could actually do the additions in any order as long as you keep the signs with the proper numbers:
30-20+2
30+(-18)
= 12
or even
30-20+2
32-20
= 12
