Changes in mean, median, mode and range
key notes :
The range is the difference between the greatest number and the least number.
Learn with an example
Look at this set of 9 numbers:
2 2 7 2 1 5 2 4 3
How would the range change if the number 2 replaced the number 7 in the set?
increase decrease no change
Find the original range. Subtract the least number from the greatest number
7-1=6
The original range is 6.
Now replace 7 with 2.
2 2 2 2 1 5 2 4 3
Find the new range. Subtract the least number from the greatest number.
5-1=4
The new range would be 4.
The range would decrease from 6 to 4.
Look at this set of 7 numbers:
88 39 96 90 37 54 96
How would the range change if the number 53 replaced the number 54 in the set?
increase decrease no change
You can solve this problem without doing any calculations. The least number in the set is 37. The greatest number is 96. Since 54 and 53 are both between 37 and 96, replacing 54 with 53 will not change the range.
You can check your answer by doing the calculations.
Find the original range. Subtract the least number from the greatest number.
96-37=59
The original range is 59.
Now replace 54 with 53.
88399690375396
Find the new range. Subtract the least number from the greatest number.
96-37=59
The new range would also be 59.
The range would not change.
Look at this set of 7 numbers:
4 6 3 4 7 2 9
How would the range change if the number 4 replaced the number 6 in the set?
increase decrease no change
You can solve this problem without doing any calculations. The least number in the set is 2. The greatest number is 9. Since 6 and 4 are both between 2 and 9, replacing 6 with 4 will not change the range.
You can check your answer by doing the calculations.
Find the original range. Subtract the least number from the greatest number.
9-2=7
The original range is 7.
Now replace 6 with 4.
4434729
Find the new range. Subtract the least number from the greatest number.
9-2=7
The new range would also be 7.
The range would not change.
let’s practice!
