SOLUTION: How do I find the sum of the first 10 posivtive integers?

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Question 175214: How do I find the sum of the first 10 posivtive integers?
Found 2 solutions by Mathtut, solver91311:
Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website!
Sum = n/2 (t1 + t2) where n = total no. of terms, t1 = first term, t2 = last term
:
remember zero is neither positive or negative

Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!
You want the sum of the integers 1 through 10.

The first number in your series is 1 and the last number in your series is 10.

The second number in your series is 2 and the second to the last is 9.

Since you have 10 numbers total, you have half that many, or 5 such pairs that add up to 11.

This works in general. If you want the sum of a series of integers, add the first number to the last number, multiply that sum by the number of numbers in the series, and then divide by 2. Symbolically:

where is the first number, is the last number, and is the number of numbers in the series.