Question 1140351
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The three terms are a, ar and ar^2.


Their product is  a*ar*ar^2 = (ar)^3 = 216;


hence, ar = {{{root(3,216)}}} = 6.


Thus the middle term of the progression is ar = 6.


3 seconds to guess two other terms: 1 and 36.


So, the progression is  1, 6, 36.


The reversed order  36, 6, 1  also works.
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