go up the number line (move to the right). When subtracting a positive number, go down the number line (move to the left). Start at \(3\) and go down \(10\). The answer is \(- 7\).

Image caption, 15 and 3, our two parts, can be swapped around and the number sentence is still correct. 3 + 15 = 18. 18 - 15 = 3 is the subtraction ... whole model and use the remaining numbers ...

A number line is a pictorial representation ... You can have them subtract one roll from the next and use the number sequences to measure probability. Also, if you take a close look at a standard ...