SOLUTION: What is [math]17+18+19+\cdots+42+43[/math] ?

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Question 985294: What is [math]17+18+19+\cdots+42+43[/math] ?
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
The main formula we are going to use here is called the Closed Form.
The sum from 1 to n is n(n+1)/2.
So Let's take the sum from 1 to 43 first. That would be 43(44)/2 = 946.
Notice that in order to get the sum from 17 to 43, we need to subtract off 1 through 16.
So the sum from 1 to 16 is 16(17)/2 = 136
So 946 - 136 = highlight%28810%29