Division: partitioning leading to short division
Spine 2: Multiplication and Division – Topic 2.15
Primary
KS2
Year 4
Mastery PD Materials
Introduction
Introduce the short division algorithm, using it to divide two-/three-digit numbers by single-digit numbers; explore exchange where necessary.
Teaching points
- Teaching point 1: Any two-digit number can be divided by a single-digit number, by partitioning the two-digit number into tens and ones, dividing the parts by the single-digit number, then adding the partial quotients; if dividing the tens gives a remainder of one or more tens, we must exchange the remaining tens for ones before dividing the resulting ones value by the single-digit number.
- Teaching point 2: Any two-digit number can be divided by a single-digit number using an algorithm called ‘short division’; the algorithm is applied working from the most significant digit (on the left) to the least significant digit (on the right); if there is a remainder in the tens column, we must ‘exchange’.
- Teaching point 3: Any three-digit number can be divided by a single-digit number, by partitioning the two-digit number into hundreds, tens and ones, dividing the parts by the single-digit number, then adding the partial quotients; if dividing the hundreds gives a remainder of one or more hundreds, we must exchange the remaining hundreds for tens before dividing the resulting tens value by the single-digit number.
- Teaching point 4: Any three-digit number can be divided by a single-digit number using the short-division algorithm.