Choosing a Method of Subtraction

You know several methods of subtraction which are:

  • Mental Subtraction
  • Paper and Pencil
  • Calculator

You should choose the method that is easiest, fastest and most accurate. It is very valuable to become proficient in all methods. A calculator is easiest but often not the fastest way to subtract. Mental math is the fastest method but not always the easiest. Using paper and pencil is necessary on complex problems that require an exact answer.

Subtracting Numbers with a calculator

Subtracting numbers (for example 68 - 45 ) with a calculator involves several steps.

Enter the first number by pressing the 6 button and the 8 button

Enter the minus operation by pressing the button

Enter the number 45 by pressing the 4 button and the 5 button

Press the = button to make the calculator determine the answer.

Find the Difference between the two Numbers.