Answer:
L = -4 + (n - 1)(0.5), where n represents which term (1, 2, 3, ... ) and L represents the last term.
Explanation:
We assume that this is an arithmetic sequence: L = A + (n - 1)D, where L is the last figure, A is the first and D is the common difference.
Here we have -2.5 = -4 + (n - 1)D, where neither n nor D is specified.
If we arbitrarily let D = 0.5, then the terms of the sequence are
{-4, -3.5, -3, -2.5}, and n = 4:
Check: If n = 4, what is the last term? L = -4 + (4 - 1)(0.5), or
L = -4 + 3(0.5) = -4 + 1.5 = -2.5
Assuming an arithmetic sequence, the pattern is
L = -4 + (n - 1)(0.5)