1 Basic Addition {App Users/Mobile Users}

The basics begin with addition and subtraction.

When you see the '+' sign you add the numbers on the left and right together.

Ex) 1+1 = 2

To add a string of numbers, it is easier to add up the numbers into 10s and 5s.

Ex)

1+2+3+4+5+6+7+8+9

⇩

1+9 + 2+8 + 3+7 + 4+6 + 5

⏟ ⏟ ⏟ ⏟ |

10 + 10 + 10 + 10 + 5

= 40 + 5

= 45

You can either add numbers in a string or you can add them into a table. It is more efficient to add them in a table when you are using large numbers.

Ex)

` ₁ ₁ ₁

` 2345 2345

` 4936 ⇒ 4936

+ 9527 + 9527

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

` 16808

The 1 above the original numbers come from adding the columns; for example 5+6+7 which equals 18 and moving the 1 from the 18 to the top of the next column while the 8 becomes the ones place of the solution. You will have to do this until you reach the end and make it to the thousandths place, where you will bring down that one to ten thousandths place and reach your final solution.

Note:

The name of moving the 1 over to the top of the next column is called 'carry', since you 'carry over' the 1. Also it is easier if you have the columns aligned and write distinct carried over numbers because it is possible to make very simple mistakes from just not writing well.