I hope this is what you're looking for. The concept of regrouping<span> (borrowing) is so that students can see what actually happens in it. For example, to </span>subtract <span>52 − 38, we write 52 as 50 + 2 (breaking it down into its tens and ones). Then, </span>regrouping<span> means that 50 + 2 becomes 40 + 12.</span>