JUNIOR HIGH MATHEMATICAL ESSENTIALS BOOK TWO CHAPTER I A NEW USE FOR GRAPHS IN PROBLEM SOLVING Heretofore you have used graphs when you wished to show number relations in an obvious or striking way. For this purpose you have used line, bar, circle, pictorial, rectangle, and distribution graphs. You have used the line graph to show temperature changes during a day or a week, the population gain or loss during a given period, the progress made in study during a school week, month, or term. The line graph may also be used to show how one value changes with another value; as, the value of a quantity of sugar at a given price per pound depends upon the number of pounds, or the wages of a laborer for a week at a given price per hour depend upon the number of hours worked. From the graph here shown you can read the cost of any amount of sugar at 10¢ a pound to 8 lb., if you observe |