How to Add and Subtract One-Digit Numbers

Let's say I wanted to add $1$ $+$ $5$. When you add one to any number, you get the next number. So here is the counting: $1$, $2$, $3$, $4$, $5$, and our answer is next, $6$. So, $5$ $+$ $1$ $=$ $6$

Another way to do this would be to count on my fingers. I have $5$ fingers on each hand. I hold out one hand, and put $1$ finger up on the other. Then, I count all the fingers, giving me: $5$ $+$ $1$ $=$ $6$.

To solve $7$ $-$ $3$, hold up $7$ fingers. Then, close 3, giving you $7$ $-$ $3$ $=$ $4$

Invalid username
Login to AoPS