Question

How do you evaluate `10+8-:2-4`?

Answer 1

Using PEMDAS you get 10

Explanation:

Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

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There are no Parenthesis, Exponents or Multiplication so we skip those steps and move on. First we divide 8 by 2 and you get 4.

Then you add 10 to 4, you get 14.

And finally, you subtract 4 from 14 to get 10.

Answer 2

`color(green)(10`

Explanation:

PEMDAS is an acronym for the words parenthesis, exponents, multiplication, division, addition, subtraction.

Given two or more operations in a single expression, the order of the letters in PEMDAS tells you what to calculate first, second, third and so on, until the calculation is complete.

`10 + 8/2 - 4 = 10 + 4 - 4 = 14 - 4 = 10`

Answer 3

`10`

Explanation:

Count the number of terms and simplify each to a single answer which will be added or subtracted in the last step.

`color(blue)(10)" "color(purple)(+" "8div2)color(green)(" "-" "4)" "larr` there are `3` terms
`color(white)(xxxxxxx)darr`
`color(blue)(10)" "color(purple)(+" "4)color(green)(" "-" "4)`

Now you could work from left to right, but take note of the fact that the last two terms are additive inverses, they add to `0`

`color(blue)(10)" " color(red)(+" "0)`

`=10`

Or:

`color(blue)(10)" "color(purple)(+" "4)color(green)(" "-" "4)`

`=" " 14color(green)(" "-" "4)`

`=" "10`