How do you find the range and the mean of a data set?
See solution.
Practice makes perfect
We are asked to compare two sets of data by comparing their mean and range. Let's find these quantities for each set of data.
Set C
Let's look at the set of data.
4.5 7.1 8.3 6.9
To find the range of the set we need to find the difference of the greatest value and the least value. We can see that the greatest value in the set is 8.3, and the least is 4.5.
Range: 8.3 - 4.5= 3.8
The range is 3.8. We can see that there are 4 values in the set. To find the mean, we will add all the values and divide the sum by 4. Let's do it!
Mean:4.5 + 7.1 + 8.3 +6.9/4 = 6.7
Therefore, the mean is 6.7.
Set D
Now let's look at the other set of data.
2.1 29.5 1.2 3.3
To find the range of the set, we need to find the difference of the greatest value and the least value. We can see that the greatest value in the set is 29.5, and the least is 1.2.
Range: 29.5 - 1.2= 28.3
The range is 28.3. Let's find the mean!
Mean:2.1 + 29.5 + 1.2 + 3.3/4 = 9.025
Therefore, the mean is 9.025.
Comparing the Sets
We can see that Set C has a range of 3.8 and a mean of 6.7. Set D has a range of 28.3 and a mean of about 9. Even when most of the values of Set D are smaller than the values of Set C, the greatest value of Set D is so big that the mean and the range of Set D are bigger than those of Set C.
