Question

find the term named in the problem.

27, 37, 47, 57,... find

a23

Answer 1

the first term is 27 or a1=27
the 2nd term is 37 or a2=37

notice the difference between them is 10
a2=37=a1+10

the 3rd term is 47 or a3=47
which is also a3=a1+2*10

looking at the "3" and "2"
replacing them for "n" and "n-1"

the nth term is an = a1+(n-1) *10

so a23=a1+(23-1)*10