What is Range?
The range is the difference between the highest and lowest numbers in a set.
It shows how spread out the numbers are.
Where is Range Used?
-
In math to understand how numbers vary.
-
In weather reports to show temperature changes.
-
In sports to compare the highest and lowest scores.
-
In science to measure data differences in experiments.
-
In business to track price changes or sales performance.
Criterion A: Knowledge and Understanding – Range
1. Basic Range Calculation
Find the range of the following numbers: 7, 12, 5, 9, 14
2. Test Scores Range
A student received these scores: 85, 92, 88, 79, 90.
What is the range of the scores?
3. Temperature Range
Temperatures recorded over five days were: 18°C, 22°C, 20°C, 24°C, 19°C.
Find the range.
4. Heights of Students
Heights of students (in cm) are: 145, 150, 148, 155, 147, 151.
What is the range in heights?
5. Finding Missing Value from Range
The smallest number is 20, and the range is 15.
What is the largest number?
6. Range in Weekly Steps
A person walked these steps: 4,800; 6,000; 5,500; 7,200; 6,800.
Find the range of the step counts.
7. Rainfall in Millimeters
Rainfall over a week was: 5 mm, 12 mm, 0 mm, 10 mm, 8 mm, 15 mm, 3 mm.
What is the range?
Criterion D: Real-Life Problems on Range
1. Rainfall Variation
The rainfall (in mm) over 5 days was: 3, 15, 6, 10, and 8.
a) Find the range.
b) What does this tell us about the weather during the week?
c) If the range increases next week, what does that suggest?
2. Classroom Temperatures
A classroom’s temperature over a week was: 20°C, 22°C, 21°C, 25°C, 19°C.
a) Find the range.
b) Does a large range suggest stable or changing temperatures?
c) How can this information help decide on classroom ventilation?
3. Range of Movie Ratings
A student rated 5 movies out of 10: 9, 6, 8, 7, 10.
a) What is the range of the ratings?
b) Do you think the student had consistent opinions? Why or why not?
c) Would you recommend using the range or the mode to describe their movie preferences?
4. Sales Range in a Shop
A shop sold the following number of items over 6 days: 50, 42, 65, 58, 49, 60
a) Find the range in sales.
b) What does the range tell you about how busy the shop was?
c) If one day had only 20 sales, how would it affect the range?
5. Range of Travel Times
Travel times (in minutes) for a student going to school for 5 days: 18, 22, 25, 17, 19
a) Find the range.
b) Was the travel time consistent?
c) How could this data help improve their morning routine?
6. Range of Student Heights
The heights of students in a basketball team are: 160 cm, 165 cm, 172 cm, 158 cm, 169 cm
a) Find the range.
b) Does a wide range suggest the players are very different in height?
c) Why might a coach want to know this information?
7. Range of Daily Profits
A small food stall earned this much each day: $120, $90, $140, $100, $130
a) Find the range of the daily profits.
b) Is the range useful for tracking financial stability?
c) What could be a reason for the highest or lowest profit days?
Answers
(Criterion A)
-
Range = 14 − 5 = 9
-
Range = 92 − 79 = 13
-
Range = 24°C − 18°C = 6°C
-
Range = 155 − 145 = 10 cm
-
Largest number = 20 + 15 = 35
-
Range = 7,200 − 4,800 = 2,400 steps
-
Range = 15 − 0 = 15 mm
Answers (Criterion D)
-
a) 12 mm
b) The weather changed a lot throughout the week.
c) It would suggest more unpredictable rainfall. -
a) 6°C
b) A larger range means more fluctuation in temperature.
c) Helps adjust fans or windows for comfort. -
a) 4
b) No, the ratings show some variation.
c) The mode may be better if you want an overall impression. -
a) 23
b) The shop had both slow and busy days.
c) The range would increase and show greater variation. -
a) 8 minutes
b) Slight variation, but fairly consistent.
c) Helps decide what time to leave to avoid being late. -
a) 14 cm
b) Yes, a wide range shows a mix of short and tall players.
c) For team strategy or uniform sizing. -
a) $50
b) Yes, it shows how steady or unpredictable profits are.
c) A special event or fewer customers may affect sales.
