CPM Homework Help : CCA2 Problem 10-63

Use any method to find the sum of the integers from $100$ through $1000$ . Describe your strategy.

Hint:

$1000 + 100 = 1100$
There are $901$ integers between $100$ and $1000$ , inclusive.

More Help:

Substitute these numbers into the formula:
$\frac{901(1000+100)}{2}$

Answer:

$495{,}550$