Question 1180291
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The sum of a geometric series with seven terms is 56,133, and the common ratio is r = 3. 
Find the first term.
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<pre>
The formula for the sum of the GP is


    {{{S[n]}}} = {{{a*((r^n-1)/(r-1))}}},


where "a" is the first term, r is the common ratio.


For this case, we have


    56133 = {{{a*((3^7-1)/(3-1))}}} = a*1093.


It gives the <U>ANSWER</U> :  a = {{{56133/1093}}} = 51.35682...
</pre>

Solved.


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If you do not like this ugly number, look and search for your error in the post,

because my calculations are correct.