IGCSE数学6 igcse第七课统计例子作为学校项目一部分被要求写下.pdf

Example • As part of a school project, Kieran is asked to write down the number of tracks on each of his CDs. His results are as follows: Frequency Table 9, 13, 9, 11, 9, 13, 11, 9, 10, 8 and 11. Wh at can he do to make the numbers easier to read or remember? Wha se can be d o make it easier to compare the numbers with others? Averages Mean Media n Mode 3 Methods to ex in your results The mean • the most common measure of average Small amount of numbers Finding the mean from a frequency table • Why? • Let’ssay… • If Kieran had 111 CDs… The Median • middle number • in numerical order Finding the median from a frequency table Total number Numerical Order Middle Number The Mode • the number which occurs most often in a set of data • One or more than one Mode in a Frequency Table Group data and modal classes • This table shows the shoe sizes of 100 people in a shop: Classes The Modal Class Mean in group data • The mean Finding the mid- • The grouped freq