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Rookin, Claude's suggestion should help you see how to get from each term to the next. The next term will be the sixth term. How can you get from the first term, 20, to the sixth term in one step? How can you get from the first term to the nth term in one step? Harley
Hi Rookin. I'll show you a similar solution. What is the nth term of 10, 5, 0, 5, 10, 15,...? First I look at the difference between adjacent terms: in each case, the right term is 5 less than the left term. That means that the second term is 5 less than the first and the third term is 10 less than the first. I suppose you could say that the zero'th term is 5 more than the first term, so it would be 15 if it was listed in the sequence. In fact, I can tell the value of the nth term just by knowing how many times to subtract five from the zero'th term. 0th term: 15  (5x0) You can solve your problem the same way, Rookin. Stephen.  


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