3 + 1
Today we're adding one. Here's a fun secret — plus one just means the next number!
Let's try three plus one. First, we write three.
Then plus one. Three plus one equals what?
Let's use a number line to find out.
Start at three. Put your finger right here.
Now hop forward one step.
We landed on four!
So three plus one equals four.
See? Plus one is just the very next number.
Three plus one is four. You've got it!