Question: The survey results of the ages of students in the Adult Basic Education Maths classes are shown in the bar graph. Find the median, lower quartile by constructing the ogive of the data.
A ) 15, 44 B ) 25.8, 20.4 C ) 21, 36 D ) 26, 15.8
Steps to derive
1 Using the data in the histogram, write the frequencies and cumulative frequencies for each class as shown.
2 Draw the cumulative frequency graph (ogive) for the data.
3 From the ogive, the median age of students in ABE maths classes is (Q2) = 25.8 years [Q2 is the 50th percentile.]
4 Q1 is called the lower quartile. So, Q1 = 20.4 [Q1 is the 25th percentile.]
