The sum of the m numbers divided by m (which is the average) equals n^2. Then, the sum of the m numbers equals mn^2.
The sum of the n numbers divided by n (which is the average) equals m^2. Then, the sum of the n numbers equals nm^2.
The average of m+n numbers which is the sum of the m numbers plus the sum of the n numbers divided by (m+n) equals (mn^2+nm^2)/(m+n). This is mn(n+m)/(m+n). Then the factor (m+n) can be ruled out and the result is mn.
I'm guessing the repeating part is 89 at the end, so that

Then





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An arguably quicker way without using geometric series:




Answer:
Graphing the derivative with the function can illustrate how to find these turning points. The function is increasing exactly where the derivative is positive, and decreasing exactly where the derivative is negative. On the graph of the derivative find the x-value of the zero to the left of the origin.
Answer:
look it up
Step-by-step explanation: