1) which of the following arithmetic sequences have a common difference of 2 1/2? a) -4,-1.5,1,3.5,6,8.5 b) 2 1/2, 4 1/2, 6 1/2, 8 1/2, 10 1/2 c) 1.5,3,4.5,6,7.5 d) -5, -3 1/2, -1 1/2, 2 2) in this arithmetic sequence, what is the common difference? 11, 8, 5, 2, 3 -3 5 -1

Answers:
1) A
2) -3

Work:
1) The answer is A because there is a common difference of 2.5 between each term, meaning that exactly 2.5 is added between each successive term of the sequence. 
2) The answer is -3 because in order to get from one term to the next in the above sequence, you must subtract 3. For instance, 11-3=8, 8-3=5, and so on. Since you are subtracting the value must be negative, giving you -3. 

Ihonestly don’t no that