Question 1097187
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{{{a[8]}}} = {{{a[1]*r^7}}}  ====>  {{{r^7}}} = {{{a[8]/a[1]}}} = {{{38.4/0.3}}} = 128.


Common ratio = {{{root(7,(38.4/0.3))}}} = {{{root(7, 128)}}} = 2.
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