SOLUTION: find the average of all add numbers below 30?

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Question 772466: find the average of all add numbers below 30?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Notice that when you start adding up odd
numbers starting with 1:
1 = 1
1 + 3 = 4
1 + 3 + 5 = 9
1 + 3 + 5 + 7 = 16
1 + 3 + 5 + 7 + 9 = 25
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So, if you have +n+ odd numbers starting
with 1, then Sum = +n%5E2+
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There are 5 odd numbers below 10
There are 4 odd numbers below 8
Following this, there are 15 odd numbers below 30
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Sum = +15%5E2+
Sum = +225+
Average = +n%5E2+%2F+n+
Average = +225%2F15+=+15+