# GRE Arithmetic - Number operations examples

The following are example arithmetic number operations, similar to those that you might expect to find on the easier math questions on the GRE.

So, you need to be familiar with arithmetic operations if you want to score well on the math section of the GRE -- that goes without saying. Also, there are a few shortcuts that you should keep an eye out for. Although there are no "tricks" that you should know of if you want to do well on the GRE, there are shortcuts that might help you to arrive at an answer quicker, or at least they'll help you eliminate wrong choices. So, become familiar with these two math concepts:

Test Tip |
There are certain key facts that you should remember when dealing with products, sums, etc. The product of 0 and any other number is always 0. If the product of 2 numbers is 0, then at least one of the numbers must be 0. |

TestTip |
The sum of any number and its opposite is always 0. For example, the sum of 4 and its opposite, -4, is 0, because 4 + (-4) = 0. |

So, a sample GRE arithmetic question that requires you to have knowledge of opposite numbers is the following:

How many pairs of opposite numbers are there which are greater than -9 and smaller than 11? |

The integers that are greater than -9 and smaller than 11 include -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10. And there are 8 pairs of opposite numbers.