Pretend you forgot how to subtract. Here are two ways explained. Which do you prefer?

I prefer the adaptation of the top one, where you subtract 1 from both numbers first, then calculate 9999 - 4571. Fun to explore both methods though!

Method no. two is how cashiers use to make change at a time when their registers didn't provided them change due information [just the total]. e.g. Suppose groceries cost $12.65. a dime makes $12.75, plus a quarter makes $13, plus $2 makes $15, plus a fiver makes $20.

Method 2! Some will call method 2 the “new math”; I call it having number sense.

Definitely adding up from subtrahend to minuend!

Frankly I like the method you showed the other day. Change the top number to 9,999 and add 1 to the result.

The 2nd method

The top one because I could easily do that one in my head. That being said, depending on what the numbers are, I might use the second system. :)

I used to call the first method “Same Difference” and emphasize that the “space between the two numbers didn’t change”. And I love love love showing my third graders the counting up method. I always say to them that adding is easier than subtracting so just “add up”