Problem
12 ,17 ,22 ,27... 50th term
Solution
for this case we know that
a1 = 12
a2= 17
We can write the general expression for the sequence on this way:
an = a1 + (n-1)d
17 = 12 + (2-1)d
17=12 +d
d = 5
And the general expression would be given by:
an = 12 + (n-1)*5
And if we replace n=50 we got:
a50 = 12 + (50-1)*5 = 12+245 =257