Arithmetic Grade Four

Lesson Twenty-five: Carrying

Take a look at this example: 

   50
  +50
  ----
  100
You know probably already that 50 + 50 = 100 without worrying about carrying or regrouping. But let's take a closer look at this problem. Adding the zeroes in the ones column gives us zero and so there's no problem there. When we add the two fives in the tens column we get 10. When we write the 10 in front of the zero in the ones column, the zero in ten winds up in the tens column and the 1 in ten winds up in the hundreds column.

Basically what happened is we carried the one to the hundreds column.

Here's another example: 

    90
   +10
   ----
   100
Here again we add the zeroes in the ones column and get 0. In the tens column we add the 9 and the 1 and get 10. We write the 10 down in front of the zero in the ones column and we get the answer 100, just like in the last example.

Try a few of these yourself.

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