Question

Is the following sequence arithmetic? If so, identify the common difference.

18, 13, 8, 3,
Yes; 10
No
Yes; 5
Yes; -5

Answer 1

D(Yes;-5) is correct.

Explanation:

Let's check 2 consecutive numbers

A(1) = 18

A(2) =13

=> common difference=A(2)-A(1) = 13-18 =-5

(Also, we see A(4)-A(3) = A(3)-A(2) =-5)