We say that a is less than b (written a , b) if the point representing a is to the left of the
point representing b on the real number line. For example, 4 , 7 because 4 is to the left of
7 on the real number line. We may also say that 7 is greater than 4 (written 7 . 4). We may
indicate that the number x is less than or equal to another number y by writing x # y. We
may also indicate that p is greater than or equal to 4 by writing p $ 4.