} Cumulative frequency “Quarter” QUARTILE:  ‘running total’ The 25% boundary is called the LOWER QUARTILE The 50% boundary is known as the MEDIAN The 75% boundary is called the UPPER QUARTILE “Quarter” QUARTILE: If we order the data and split it into 4 parts: The first 25% Between 25% and including 50% Between 50% and including 75% The last 25% Then a QUARTILE is the name of each of the boundaries 25%, 50% and 75%. } of the data The interquartile range looks at the middle 50% of the data Upper Quartile (75%) – Lower Quartile (25%)

Using the graph, find the Class 9a made a table showing the size of the students’ shoes in Year 9 Shoe Size Frequency Cumulative Frequency 3 1 3.5 4 4.5 5 13 5.5 6 12 6.5 7 8 7.5 2 8.5 9 9.5 10 How many people where in the class all together? The cumulative frequency is a running total. Fill in the table and then use the table to plot the graph. Using the graph, find the (1) median, (2) lower quartile, (3) upper quartile, (4) interquartile range.

The cumulative frequency is a running total In a certain school, 38 pupils took the maths SAT's exam (2006) The results are shown in the table. Level 5 6 7 8 Number of pupils 11 13 10 4 Cumulative frequency Fill in the table and draw the graph Using the graph, find the median lower quartile upper quartile interquartile range.

The year 9’s were ordered in years of age (in years). 13.2,13.2,13.2,13.2,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,3.3,13.3,13.3, 13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.4,13.4,13.4, 13.4,13.4,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5, 13.5,13.5,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6, 13.6,13.7,13.7,13.7,13.7,13.8,13.8,13.8. Age 13.2 13.6 Number of pupils Cumulative frequency Copy and complete the table into your book Draw a graph of the cumulative frequency in your book. Using the graph, find the (1) median, (2) lower quartile, (3) upper quartile, (4) interquartile range.

Fill in the table and draw the graph Using the graph, find the Class 9a also made a table showing the showing their heart rate before exercise Heart rate Frequency Cumulative 41 - 50 2 51 - 60 12 61 -70 20 71 -80 13 81 - 90 8 91 - 100 7 101 - 110 3 111 - 120 Fill in the table and draw the graph Using the graph, find the (1) median class, (2) lower quartile class, (3) upper quartile class.

Ext: The length of some leaves were measured http://www.channel4.com/learning/microsites/H/homeworkhigh/maths/answer.jsp?id=891