Should one put a comma before an arithmetic operation? What about long expressions?
Example: The final distance is equal to the initial distance plus initial velocity multiplied by time, plus half the acceleration multiplied by the square of time.
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Sign up to join this communityShould one put a comma before an arithmetic operation? What about long expressions?
Example: The final distance is equal to the initial distance plus initial velocity multiplied by time, plus half the acceleration multiplied by the square of time.
The secret to writing about mathematical equations is to describe the equation as a whole. I would do it this way:
The final distance is equal to the sum of three parts: 1. the initial distance, 2. initial velocity multiplied by time, and 3. half of the acceleration multiplied by the square of time.
Whenever possible, I would follow the written description by showing the equation.
There's a reason equations are best represented by symbols. I don't think mere punctuating it correctly will see you all the way through. I must suggest paraphrasing:
The final distance is equal to the initial distance added to the sum of the initial velocity multiplied by the time taken and half the acceleration multiplied by the square of the time taken.
As Edwin pointed out in his comment, commas aren't gonna cut it, you'll have to bring brackets into the mix to avoid ambiguity. And since the usage of brackets in English and in math is vastly different, it would look odd.
I would be extra careful about this, in many European countries you write one-thousand and 2/10ths as follows:
1.000,2
And In North America:
1,000.2
If you want tot write five-thousand Francs:
₣5.000
But you write five thousand dollars,
$5,000
Thus the arithmetic operations get complicated if you do not obey the cultural norms.