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I am going to call the average A so
So, for example if the total T is 75 and the number of numbers N is 5 then
For aother example suppose you know that the total is 54 and the average is 18. What is the number of numbers n? Since I know that
I know that
Multiply both sides by N to get
so
Now for your problem you know that N = 6 and A = 84. What is T? I hope this helps,
Cecil, The average (A) is the total (T) divided by the number (N) of items. A = T/N. If you want to know the total T then we "solve" this equation for T: T = A * N. So the total is the average times the number of items. Cheers,  


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