Data · JHS1 Mathematics

Lesson notes

Learning Objectives

Indicator: B7.4.1.2.2 - Calculate the median for a given ungrouped data and use it to solve problems

By the end of the lesson, learners can:

arrange a given set of ungrouped data in ascending order to form an array
identify the middle value(s) of an ordered data set
calculate the median for data sets with an odd number of values
calculate the median for data sets with an even number of values by averaging the two middle numbers
determine the median from a frequency table and use it to solve simple problems based on real-life data

Sign in with your phone number to read the full note and download the GES plan - free.

Sign in with phone number

Curriculum details

Strand: Handling Data (Strand 4)
Sub-strand: Data (4.1)
Content standard: B7.4.1.2 - Determine the measures of central tendency (mean, median, mode) for a given ungrouped data and use it to solve problems
Indicator: B7.4.1.2.2 - Calculate the median for a given ungrouped data and use it to solve problems
Suggested placement: Term 3, Week 11 (Week 35 of the year)
Our suggestion, laid out in curriculum order across three terms of twelve weeks. NaCCA does not fix the week, so follow your school's scheme of learning.
Curriculum reference: Mathematics, Common Core Programme (JHS1-JHS3), 2023, p. 84
Transcribed from the official NaCCA publication. Check this page against the source.

Exemplars (from the NaCCA curriculum)

E.g. 1 Find the median for a data set by arranging the items in the set in an array and identifying the middle item.
i. Find the median of 19, 29, 36, 15, and 20. (i.e. the middle item in the array 15, 19, 20, 29, 36 is 20). NB. since there are 5 values (odd number), 20 is the median (middle number)
ii. Find the median for the data set 8, 9, 7, 6, 8, and 10. (i.e. the middle item in the array 6, 7, 8, 8, 9, and 10 is 8). NB. since there are 6 values (even number), we must average those two middle numbers to get the median value
E.g. 2 Find the median for a data set (in a frequency table).
iii. Find the median mark obtained in a mathematics class test presented in the frequency table:

Wide black-and-white mathematical teaching visual is organised as a table with horizontal divisions, vertical... — A wide black-and-white mathematical teaching visual is organised as a table with horizontal divisions, vertical divisions. Visible labels, values, and notation include: Score; Frequency; 1; 2; 6; 3; 4; 5.

Score 1 2 3 4 5 Frequency 2 6 4 5 3 NB. Since there are 20 values, the 10 th and 11 th scores are the middle numbers and they are both 3, so the median value is 3.
iv. Find the median ages of children at a party presented in the frequency table:

Ages (x): 1 3 5 6 7 8 9 Frequency (f): 2 5 6 10 8 5 3
NB. Since there are 39 values, the 20 th age is 6, so the median value is 6.