Question

What is the 23rd term of the arithmetic sequence where a1 = 8 and a5 = 22?

Answer 1

a23=85

Answer 2

You have to find the common difference.
a1 = 8 and a5 = 22. Difference = 14 so you can have 3 values in between.
a2 = 11.5, a3 = 15, a4 = 18.5, a5 = 22, a7 = 29, a9 = 36, a11 = 43 and so on.
Keep adding 7 for the odd-numbered terms. (Common difference is 3.5)
a23 = 85.

Answer 3

Is there no formula for it?

Answer 4

Read mine :P

Answer 5

That cant be the answer tho! i dont understand what a23 = 85 means... explain?

Answer 6

It is the answer!

Let me try to explain..

Answer 7

The formula for the sum of a finite arithmetic sequence is [# terms/2](first term + last term).

Answer 8

Does that help at all.? I hope it does.

Answer 9

It does thankyou!