First term [ a ] = 6.3
Common difference [ d ] = 8.8 - 6.3 = 2.5
Using general term formula,
[tex]t_{n} = a + (n-1)d[/tex]
78.8 = 6.3 + (n-1)*2.5
2.5*(n-1) = 72.5 [ Dividing both sides by 2.5 ]
n-1 = 29
n = 30
Hence, 78.8 is the 30th term in the arithmetic series.
