SOLUTION: Please help me solve this question. What is the average of 3^22, 3^23 and 3^24

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Question 62663: Please help me solve this question. What is the average of 3^22, 3^23 and 3^24
Found 3 solutions by joyofmath, uma, jai_kos:
Answer by joyofmath(189) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me solve this question. What is the average of 3^22, 3^23 and 3^24
Let the three numbers to average be a, b, and c.
So, a=3%5E22.
Then a%2A3=3%5E%2822%2B1%29=3%5E23=b.
Also, a%2A3%2A3=3%5E%2822%2B2%29=3%5E24=c.
So, b=3%2Aa and c=9%2Aa.
So, the three numbers to average, in terms of a, are a, 3*a, and 9*a.
You get the average of three numbers by adding them up and dividing by 3.
So, the average is: %28a%2B3a%2B9a%29%2F3+=+13a%2F3.
Put a=3%5E22 back into the equation and the average is: 13%283%5E22%29%2F3.
But, 3%5E22%2F3+=+3%5E21 so the average is 13%283%5E21%29.

Answer by uma(370) About Me  (Show Source):
You can put this solution on YOUR website!
The average of any set of numbers is = sum of the numbers/No: of values
So the average of 3^22, 3^23, 3^24 = (3^22 + 3^23 + 3^24)/3
= (3^22 + 3*3^22 + 3*3*3^22)/3
= 3^22(1 + 3 + 9)/3
= 3^22(13)/3
= 3^21(13) [when divided, the exponents are subtracted]
So the average = 13(3^21)
Good Luck!!!

Answer by jai_kos(139) About Me  (Show Source):
You can put this solution on YOUR website!
Given 3^22, 3^23 and 3^24
We find that the base is same, only the powers are different.
3^22 + 3^23 + 3^24 = 3^ (22 + 23 + 24)
= 3^ (69)
THe average is given by the total number divide the number of terms.
Average = 3 ^ 69 / 3 ^ 3
Since there are 3 terms.
Average = 3 ^ (69 / 3)
= 3 ^ 23
Therefore the average is given by 3 ^ 23