SOLUTION: the average of cosecutive natural numbers from 1 to 49 is?

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Question 909150: the average of cosecutive natural numbers from 1 to 49 is?
Answer by Theo(13342) About Me  (Show Source):
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there are 49 numbers because 49 - 1 + 1 = 48 + 1 = 49

formula for the sum of an arithmetic sequence is n * (a1 + an) / 2

this becomes 49 * (1 + 49) / 2 which becomes 49 * 50 / 2 which becomes 49 * 25 which becomes 1225.

the average is the sum divided by the number of items which becomes 1225 / 49 which becomes 25.

the average is 25.