Rules for Addition and Subtraction of Numbers

If both numbers are positive, add the numbers and keep the positive sign.

ex.

If both numbers are negative, add the numbers and keep the negative sign.

ex.

If one number is positive and the other negative, subtract the smaller number from the larger number and keep the sign of the larger number.

ex.

Rules for Multiplication and Division

If both numbers are positive, the result is positive. ,

ex.

If both numbers are negative, the result is positive. ,

ex.

If one number is positive and one number is negative, the result is negative.

, , ,

ex.