Les drew the number line shown to add 2.5 + (–25). he says the sum is 22.5. which is a correct description of his work? a. his number line is correct, and the correct sum is 22.5. b. les should have started at 0, moved right to 2.5, and then moved left to –25. the correct sum is –23.5. c. les should have started at 0, moved right to 2.5, and then moved left 25 units. the correct sum is –22.5. d. the correct sum is 22.5, but his number line is incorrect. les should have started at 0, moved left to –2.5, and then moved right 25 units.