Subtracting Two-Digit Numbers With Regrouping

Khan Academy

This instructional video provides a comprehensive tutorial on subtracting two-digit numbers involving regrouping (often called borrowing). The narrator walks through a single problem, 83 minus 25, demonstrating that standard subtraction in the ones column is impossible without modifying the place values. The video breaks down the solution using three distinct methods: the standard vertical algorithm, expanded form with numerical values, and expanded form using place value language (tens and ones). The central theme of the video is conceptual understanding of place value over rote memorization. By showing the same operation in three different formats, the video reinforces that "borrowing" a one is actually moving a value of ten from the tens place to the ones place. It explicitly connects the abstract crossing-out of numbers in the standard algorithm to the concrete values they represent (e.g., turning 80 into 70 to make 3 into 13). For educators, this resource is an excellent tool for introducing or remediating two-digit subtraction. It is particularly valuable because it addresses the common student struggle of "top number is smaller than bottom number" by explaining the logic behind regrouping rather than just the procedure. Teachers can use this video to transition students from concrete manipulatives to the abstract vertical algorithm, using the middle segment on expanded form as a bridge to show exactly where the "1" comes from when regrouping.