# Question Video: Subtracting Numbers up to 10 by Counting Back

There were 9 balls in a box. Then, 5 of them were removed. How many balls are left?

02:13

### Video Transcript

There were nine balls in a box. Then, five of them were removed. How many balls are left?

This is a word problem. Let’s look carefully at the information we’re given. To start with, we’re told that there are nine balls in a box. Then, five of them were removed. If the balls were removed, that means they were taken away. We have to work out how many balls are left.

Have you worked out what kind of problem this is? When we have a number of balls and we take some away, we need to subtract. So, there were nine balls in a box. And five were removed or taken away. To find out how many balls are left, we need to take away five from nine. Let’s use a number line to help us subtract.

We need to start at number nine because there were nine balls in the box at the start. We have to take away five. That means we need to count backward five starting at number nine. One, two, three, four, five. Nine, eight, seven, six, five, four. Nine take away five equals four. To help us subtract, we started at number nine on the number line and we counted back five. If there are nine balls in a box and five of them are removed, there will be four balls left. Nine subtract five equals four.