SOLUTION: If a2=15 and a9=39, what is a16?

Algebra ->  Sequences-and-series -> SOLUTION: If a2=15 and a9=39, what is a16?      Log On


   



Question 1039329: If a2=15 and a9=39, what is a16?
Answer by chen.aavaz(62) About Me  (Show Source):
You can put this solution on YOUR website!
This is an arithmetic sequence with common difference d, which can be calculated as follows:
Number of terms from a2 to a9: 7, so the total difference for 7 terms is
7%2Ad=39-15=24
Similarly, from a9 to a16 we have again 7 terms, so the total difference will again be 24.
Therefore: a16=a9%2B24=63