Intermediate Mathematics

Pictograph - A pictograph uses pictures or symbols to compare data.

This pictograph shows the number of boxes of candy sold by Ace Candy Emporium during four months.

To interpret the information on a pictograph, it is necessary to read the key and note the quantity represented by each symbol on the graph.

To determine the number of boxes of candy sold in February, first notice the key. The key shows that each symbol is equal to 1,000 boxes.

Next, find the label for February on the graph and count the symbols next to it. Since there are 5 symbols next to "February," the graph indicates there were 5 × 1000 boxes of candy sold in February.

The graph shows that 5,000 boxes of candy were sold in February.

Because pictographs compare data, questions relating to pictographs often ask you to compare the quantities shown by the pictures.

This pictograph compares the number of boxes of candy sold for each of four months. If you were asked how many fewer boxes were sold in March than in February, you would need to find the rows labeled "February" and "March."

In this graph, there are 3 more symbols for February than for March. Since each symbol represents 1,000 boxes, there were 3 × 1000 fewer boxes sold in March.

The graph shows that 3,000 fewer boxes of candy were sold in March than in February.

Sometimes the symbols on a graph are not complete symbols. When this happens, you must estimate the value the picture is trying to show.

This pictograph shows the votes by students at Randolph Academy for their favorite kind of book.

The key shows that each symbol represents 50 student votes. Next to "Mystery," there are 2 complete symbols and part of another. This means that \(2\frac{1}{2}\) × 50 students voted for mystery books as their favorite.

There were 125 students who voted for mystery books as their favorite.