Question

What is the 74th term of this arithmetic sequence?
-25, -21, -17, -13,-9, -5,...

Answer 1

267

Explanation:

let's say that

f(0)=-25

so in the sequence we are adding 4

so f(1)=-25+4=-21

and f(2)=f(1)+4=-25+4+4=-25 + 4(2)

so if you continue you will notice that

f(n)=-25+4(n)

so our question is

What is the 74th term of this arithmetic sequence?

so if f(0) is our first term, the 74th will be f(73)

so we can apply our formula

f(73)=-25+4(73)

=-25+292

=267