Greg was adding two numbers on a number line. He started at +4 and then he added –6. He wrote that his answer was –2. Is Greg's answer reasonable?
a.No, it is not reasonable because when you add two numbers you get a number greater than either of the two numbers. The answer is +10.
b.No, it is not reasonable because you subtract the smaller number from the larger number to get +2.
c.Yes, it is reasonable because if you start at +4, you will move 6 spaces to the left to get –2.