Problem Solving (PS) | Re: What is the sum of the integers from 1 to 999 , inclusive?

Sum = number of terms * mean

- # of terms = (999-1), but we need to add '1' to the resultant as this is an inclusive set, bringing us back to '999'.
- mean of the set = first term+last term divided by 2 which gives us 500 (1+999 = 1000/2 = 500)

Putting it into the original equation:
- sum = 999 (number of terms) * 500 (mean) = 499500

Hope that helps!

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