DM and AS go from left to right. Like Vezon said, order doesn't matter. The only way you'll get confused is if you don't pay attention to minus signs. 3 - 4 + 5 - 10 != 4 - 3 + 10 - 5. Subtraction is addition of a negative, so it would be (-4) + 3 - 10 + 5. And I guess it's the same with division. They aren't commutative, but 4 / 8 x 6 / 10 is in essence 4 * 1/8 * 6 * 1/10, which is commutative. I'm basically done doing 'division' nowadays. In so many instances, it's easier to see it at multiplication of a number over 1 (for example, unless you have a 1st order polynomial in the denominator, it's almost always easier to use the product rule instead of the quotient rule for derivatives).