1. Statistics lesson 1 examined in the summer Introduction to statistics The mean Finding the mean from a frequency table

2. Introduction to statistics The following shows the test results for 10 students ABCDEFGHIJ S16498857899 M17898685889 How can we compare the test results ? The mode is the most frequent value. The median is the middle number when the values are ordered. The mean is the total of the values divided by the number of values. The range is the largest - the smallest value We could calculate some statistics for the test results.

3. ModeMedianMeanRange S1 M1 ABCDEFGHIJ S16498857899 M17898685889 Conclusions?

4. A set of data with 8 values has ∑x = 24 Find the mean value

5. The mean of a sample of 25 observations is 6.4. The mean of a second sample of 30 observations is 7.2. Calculate the mean of all 55 observations

6. Worksheet Do the Ex B qs

7. Finding the mean from a frequency table Answer: mean = 416/21=19.809..=19.8 to 3sf xf 122 176 208 254 301 Now do Ex C qs 1-3

9. Find an estimate for the mean of this set of data x frequency 2≤x<4 2 4≤x<6 3 6≤x<8 7 8≤x<10 4 10≤x<12 1 Grouped frequency table