SOLUTION: Sum of 3 nos.in g.p. is 21 and sum of their squares is 189.find 3 nos.

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Question 868087: Sum of 3 nos.in g.p. is 21 and sum of their squares is 189.find 3 nos.
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196
1 2 3 4 5 6 7 8 9 10 11 12 13 14
squares up to 200
21=t*(1 - r^3)/(1 - r)
3+6+ 12=21
9+ 36+144=189
The numbers are 3, 6 12