SOLUTION: If 7,m,n,189 are in gp, find m and n

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Question 1182541: If 7,m,n,189 are in gp, find m and n
Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.

189 is the 4th term of the GP, THEREFORE

    189 = 7*r^3

    r^3 = 189/7 = 27

    r = root%283%2C27%29 = 3.


Hence,  m = 7*3 = 21;   n = 21*3 = 63.      ANSWER

Solved.