## Tuesday

### Addition and Subtraction on Number Lines

Here's how to add two numbers together: Count on from the biggest number.

If you have a ruler near by, you can use that! Start at the larger number and count on using the ruler just like the line in the video.

You can use the same method on a number line for subtraction by starting from the largest number and counting back:

Try this game for subtracting using pictures: Apples on the Tree Take Away.

Journey to Ancient Egypt and defeat the Mummy: Crocodile and Mummy Number Lines.

Also try counting on and solving these equations: Count on.

Shoot fruit to solve additions and subtractions on number lines.

Use a number line to solve these problems. Grab a ruler or draw one yourself - it should look like this:

Try adding (one number and another number):
6 plus 5 5 plus 6 8 and 7 7 and 8 6 + 4 4 + 9
Should you start counting on the number line from the 9 or the 4? Is it quicker to start from 9 or 4?
3 + 8 (start from the 8!)
2 + 10 (start from 10!)
4 + 13 (start from 13!)
Pick the larger number to start counting from:
7 + 9
12 + 8

Now try subtraction (a bigger number take away a smaller number):
7 take away 5
7 take away 2
9 take away 4
9 take away 5
12 take away 7
13 take away 6
17 take away 9

Now you're ready to play: Feed the aliens.