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tiffanym
Find the 15th term of the arithmetic sequence. 2, 3.5, 5, 6.5, ...
0.5+(n*1.5) where n is the nth term
you need to find the common difference d as the 1st term a= 2 and the number of terms n = 15 then use the formula \[T _{15} = 2 + (15 -1)\times d \]