0? You're right. Simple. That's it. Minus 2 plus 2 equals 0. He just filled the hole. Neither the Greeks nor the Romans were capable of using the concept of zero. It was your ancestors, the Mayas, who first contemplated the zero. The absence of value. True story. You burros have math in your blood.
No problem. Glad to help. I've done the same thing myself a few times assuming that the source material on the internet would be error-free.
About the numbers though - that's a general rule of thumb. But the rules can change depending on who the audience is and the formality of the writing. For example, when I submit articles to scientific journals, some require numbers <10 to be written out - others require numbers <20 to be written out
@weesin thanks for the suggestions. they were very helpful! I did mean "Mayans," and I didn't know that about numbers. I copy-pasted the quote from the internet, and I didn't read it as thoroughly as I should have.
I believe you mean 'mayans' not 'mayas'. Also, there is inconsistency in your quote. At times, you type out the word 'zero' - other times, you use the digit. As a general rule of thumb, numbers <10 should be written out