Think of a trip that you or a friend might take frequently, such as shopping or going to work. How long would you say that trip takes?
You may have said something like, "Well, it usually takes about 45 minutes to get to work, but, if the traffic is heavy, it can take up to hours.” In other words, 45 minutes is a typical time, though there are exceptions. How did you decide what time to say? Did you pick a time that seemed to occur quite often, or perhaps a time that was somewhere in the middle of the times taken for recent trips?
Knowing a typical value for a data set, and also how the data is spread out around this typical value, is important for all sorts of situations.
A value that is typical of the values in a set of data is known as an average. There are different ways of calculating an average, and you will learn about three of these: The mean, the median, and the mode.