Reading a pictograph

In your book, Maths Mela (Chapter 15, Data Through Pictures), Joseph Uncle wants to show the toys, board games and sports items in his shop as a pictograph. But he has too many items to draw one picture for each. His helper Dipesh has an idea: use one picture, called an icon, for every 5 items. This is called a scale. A scale lets us show a large number of things with fewer icons.

Dipesh's pictograph has 8 icons for toys, 10 icons for board games and 12 icons for sports items, with 1 icon = 5 items. To read it, multiply the number of icons by the scale. Toys: 8 × 5 = 40. Board games: 10 × 5 = 50. Sports items: 12 × 5 = 60. In all, 40 + 50 + 60 = 150 play items.

Deepti counts the two-wheelers passing her house in one hour on three days. In her pictograph, 1 icon = 3 two-wheelers. Monday has 8 icons: 8 × 3 = 24. Wednesday has 4 icons: 4 × 3 = 12. Friday has 12 icons: 12 × 3 = 36. Friday had the most. In all, she counted 24 + 12 + 36 = 72 two-wheelers.

To compare rows, first turn icons into numbers. Wednesday had 24 − 12 = 12 fewer two-wheelers than Monday. Friday had 36 − 12 = 24 more than Wednesday. Be careful: Monday has only 4 more ICONS than Wednesday, but each icon stands for 3, so that is 12 two-wheelers.