Let's find out if it's an arithmetic sequence: 2nd term - 1st term = (-22) - (-16) = -22+16 = -6 3rd term - 2nd term = (-29) - (-22) = -29+22 = -7 No, it's not because we didn't get the same thing for both of those subtractions. If it had been an arithmetic sequence those would have had to be the same common difference and also 4th term - 3rd term = (-37) - (-29) = -37+29 = -8 would have had to have been the same common difference. So this is not an arithmetic sequence. Edwin