**Frequency Polygons**

These are just used to represent grouped data. You take the mid-interval value of each class and draw a straight line between each of the points you plot.

So for this table:The graph would be this:Easy!**Two Way Tables**

These show two types of info in the same table…and can help you to work out tricky questions.**Example:** 150 men and 150 women were asked if they are left handed. 45 people altogether were left handed. 120 women were right handed. How many men were right handed?*First make a two way table like the example below with the info you have:*Then you can work through the missing squares on the table by adding and subtracting: