Answer:
10
Step-by-step explanation:
You want the value of 20 -3×6 +8.
Order of operations
As you have noted, the multiplication is the first operation to perform when evaluating this expression. Then it becomes
20 -18 +8
Addition and subtraction are done left to right in their order of appearance.
20 -18 +8 = (20 -18) +8 = 2 +8 = 10
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Additional comment
There is a tendency to think of the ...AS as meaning the addition comes before the subtraction. In fact, addition and subtraction have the same priority, so are done in order of appearance.
Another way to think of it is that subtraction is addition of a negative number. In that sense, you can do the operations in the order you show, but the result will be ...
20 +(-18) +8 = 20 +(-18 +8) = 20 +(-10) = 10
In other words, the minus sign applies only to 18, not to (18 +8).
Likewise, ...MD... or ...DM... is often construed to mean that multiplication is done before division, or vice versa. These operations have the same priority, so are done in order of appearance.
This can be further confused by the tendency of some authors (and calculators) to evaluate "juxtaposition" as higher priority than division:
6/3(2) = 1 . . . . . PEJMDAS (juxtaposed 2 and 3, no multiplication symbol)
6/3·2 = 4 . . . . . PEMDAS
Your calculator can give you the correct answer, especially if you always use a multiplication symbol.
