**A number model in math is a sentence that illustrates how the parts of a number story are related.** The equation may include addition, subtraction, division and multiplication and may be expressed as words or in number form.

Number models expressed in number form include 6 + 7 = 13, 12 * 6 = 72 and 24 / 3 = 8. An example of a number model written in words would be, "The area of rectangle A is equal to the product of sides D and E." The same equation can be expressed in numbers as area = d * e.