An ‘ordered pair’ is simply two numbers in a certain order. For example, the numbers ‘2’ and ‘3’ can form two ordered pairs:  2, 3 and  3, 2.   Ordered pairs can also contain the same number twice. For example:  2, 2  and  3, 3

A very important application of ordered pairs is to locate points on a grid or map. For street maps it is common to use a letter and a number, eg: B17 or D5. This is not very accurate, but if two numbers were used instead of a number and a letter, then people would easily get them in the wrong order and get lost!  In mathematics, we use two numbers to accurately locate a position on a rectangular grid.  Eric has been doing ordered pairs in school and used worksheets to make several pictures.  Foghorn Leghorn was one of his more complicated graphs.