Averages in Frequency Tables
Frequency tables are dead useful for organising data - they're basically charts that show you what items appear and how often they pop up. You'll see two columns: one listing the items (like ages or favourite colours) and another showing how many times each item appears (the frequency).
These tables work brilliantly for both quantitative data (numbers like test scores) and qualitative data (categories like favourite subjects). They make messy data much easier to understand at a glance.
Finding the mode is dead easy - just look for the item with the highest frequency. Remember, your answer always comes from the items column, not the frequency column!
To calculate the mean from a frequency table, you need to be a bit clever. First, multiply each item by its frequency to create a new column. Then add up all these products and divide by the total frequency. In the swimming club example, the mean age works out to 11.2 years.
Quick Tip: When finding the mean, always multiply first, then add everything up, then divide - don't try shortcuts!