Question 1100400
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Hey, 


I solved similar &nbsp;(<U>TWIN</U>) &nbsp;problem for you &nbsp;30 minutes ago at this link:


https://www.algebra.com/algebra/homework/Sequences-and-series/Sequences-and-series.faq.question.1100391.html



Read attentively that solution. &nbsp;It is your &nbsp;<U>SAMPLE</U>.


Then substitute your data and make calculations on your own.


Prove that you do understand and can reproduce what was explained to you once.



&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;It will be &nbsp;<U>GOOD EXERCISE</U>&nbsp; to you.