Multiplication and Division Concepts 119Repeated Subtraction Division
CONCEPT:
What is the Repeated Subtraction Division Concept?
When we divide, we fi nd the number of times a number is
divisible; the result is the quotient. The number that is divided
is called the dividend. The number that divides the dividend
is called the divisor. Because subtraction and division are
interrelated operations, we obtain the same results by repeated
subtraction. For example, 15 ÷ 3 can be solved by subtracting.
Groups of 3 are subtracted from the dividend until zero is
reached. We keep track of how many groups are subtracted to
fi nd the quotient. Some students are encouraged to memorize
division facts before they understand the concept of division.
Working with repeated subtraction as a way to understand
division builds necessary foundations for students.CCSS
Operations and Algebraic ThinkingFormative Assessment
To fi nd out if a student understands repeated subtraction
division, give him the following repeated subtraction
equations and ask him to give the related division equation.
16 – 4 – 4 – 4 – 4 = 21 – 7 – 7 – 7 =
If the student is successful, provide the following division
equations and ask the student to give the related repeated
subtraction equations.
35 ÷ 5 = 56 ÷ 8 =
If the student is not successful with either set of problems, try
subtracting groups of two, fi ve, or ten. If he is successful with
both sets of problems, try more complex problems.