Mentally Subtracting Two-Digit Numbers

How to mentally subtract two two-digit numbers.

  • Subtract 35 from 84.
  • First subtract the two tens' place digits (8 - 3 = 5)
  • Notice that the bottom ones' digit is larger than the top ones' digit. Decrease the answer for the tens' place by one (5 - 1 = 4) and increase the top ones' place value by 10 (4 + 10 = 14).
  • Next subtract the two ones' place values (14 - 5 = 9)
  • Combine the tens' and ones' place differences to make 49.
  •  
  • Subtract 62 from 94.
  • First subtract the two tens' place digits (9 - 6 = 3)
  • Next subtract the two ones' place digits (4 - 2 = 2)
  • Combine the tens' and ones' place differences to give the answer of 32

Find the Difference between the two Numbers.

  -     =     

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