SOLUTION: find two geometric means between 7 and 15.379

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Question 701340: find two geometric means between 7 and 15.379
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
two geometric means between 7 and 15.379:

an=a1%28r%29%5En-1
a4=7%28r%29%5E4-1
15.379=7%28r%29%5E3
15.379%2F7=r%5E3
2.197=r%5E3
r=root%283%2C2.197%29
r=1.3

r=1.3 is the ratio, so you multiply 7 by 1.3 (which equals 9.1), giving you the first of the two geometric means, and multiply 9.1 by 1.3 (which equals 11.83) to get the second of the two geometric means

Final answer: 9.1,11.83

Multiplying 11.83 by 1.3 gives you 15.379, so it is correct.