Mode, median an range模式中位数和范围

1、mode, median and rangeaim:to find the mode, median and range, and the modal class for grouped data.put these numbers in numerical order with the smallest first. 7, 3, 9, 2, 10, 8, 5, 4, 14, 122,3, 4, 5, 7, 8, 9, 10, 12, 14,34, 67, 38, 19, 44, 57, 24, 31, 62, 2019, 20, 24, 31, 34, 38, 44, 57, 62, 672

2、, -3, 1, 4, -4, 0, 5, -2-51-4-3-20245-4-3-2 -1023451averagesan average is a useful statistic because it represents a whole set of values by just a single or typical value. where have you heard the word average before? where have you seen it used?the model the mode is a type of averagel the mode is t

3、he value that occurs most often in a set of dataexample5, 6, 8, 2, 4, 5, 3, 5mode = 5sometimes there is no mode because either all the values are different, or no single value occurs more often than other valueslwhat letter does your first name begin with?what is the mode first letter for a name in

4、class 7y2?the mode doesnt have to be a numbermode, median and rangelaim: to find the mode, median and range, and the modal class for grouped data.page 52exercise 5aquestion 1the modethe medianlthe median is another type of averagelthe median is the middle value for a set of data when the values are

5、put in numerical order.example6, 8, 3, 7, 5, 2, 4 in order2, 3, 4, 5, 6, 7, 8median = 5for an odd number of values in data set, there is only one middle value.this is the median.what is the median test score for the following set of results?5, 7, 7, 8, 10, 12, 14, 15for an even number of values in a

6、 data set, there are two middle values.the median is the value in the middle of these two values.median = 9lthe medianpage 51exercise 5aquestion 2the rangelthe range is not an average.lthe range of a set of data is the largest value minus the smallest value.lit shows how the data is spread out.a sma

7、ll range shows that the values in a set of data are similar in sizea large range shows that the values differ considerablyfind the range:what number month were you born in?range = largest number smallest numberrange =what does this tell us about the birthdays of class 7y2?for example, january = 1, j

8、une = 6, and december = 12lthe rangepage 51exercise 5aquestion 3modal classfor grouped data such as the example below, we cannot find the mode.time (mins.)frequency0-223-546-839-111instead, we find the modal class. this is the group that occurs most often.modal class = 3-5why isnt it possible to calculate an exact mode or median from grouped data?lmodal classpage 52exercise 5aquestion 6write down:5 numbers with a mode of 77 numbers with a median of 37 numbers with a mod