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Adding Tens

How to add two-digit numbers (for example 40 + 50).

  • Place one number above the other so the tens' place digits and ones' place digits are lined up. Draw a line under the bottom number.
  • 40
    50
    
  • Add the two ones' place digits. (0 + 0 = 0). Place the zero below the line in the ones' place column.
  • 40
    50
     0
    
  • Add the numbers in the tens' place column (4 + 5 = 9) and place the answer below the line and to the left of the ones' place sum
  • 40
    50
    90





Practice

Find the Sum of the two Numbers.

  =    


You have correct and   incorrect.  This is percent correct.

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