Find the missing term of each arithmetic sequence.

Question

1.) 23, ?, 49

2.) 29, ?, 33

Answer 1

49-23 = 26

26/2 = 13 = common difference

23+13 = 36 is the missing term

33-29 = 4

4/2 = 2

29+2 = 31 is the missing term

just take the average to the two terms in each problem

(49+23)/2 = 72/2 = 36

(33+29)/2 = 62/2 = 31

Answer 2

1. Let d = common difference

Then, 2nd term = 23 + d and third term = 23 + 2d

Since 23 + 2d = 49, we see that d = 13

So, the 2nd term is 23 + 13 = 36

Do problem 2 in a similar manner.