Answer:
[tex]Mean = 9.3[/tex]
Step-by-step explanation:
Given
Let accidents reported be represented by x and the frequency be represented by f
x ----- f
0-5 -- 9
6-10 -- 10
11-15 -- 6
16-20 -- 6
Required
Calculate the Mean;
To calculate the mean of a grouped data, the first step is to calculate the midpoint of the observation;
When x = 0 - 5
Midpoint = 0.5(0 + 5) = 0.5 * 5 = 2.5
When x = 6 - 10
Midpoint = 0.5(6 + 10) = 0.5 * 16 = 8
When x = 11 - 15
Midpoint = 0.5(11 + 15) = 0.5 * 26 = 13
When x = 16 - 20
Midpoint = 0.5(16 + 20) = 0.5 * 36 = 18.
So, the new table is as follows;
x ------- f
2.5 ---- 9
8 ----- 10
13 ------ 6
18 ------ 6
Mean is calculated by ∑fx/∑f
Where ∑fx represent sum of the product of f and x
∑f represent sum of frequency
∑fx = 2.5 * 9 + 8 * 10 + 13 * 6 + 18 * 6
∑fx = 288.5
∑f = 9 + 10 + 6 + 6
∑f = 31
So,
[tex]Mean =\frac{288.5}{31}[/tex]
[tex]Mean = 9.3064516129[/tex]
[tex]Mean = 9.3 (Approximated)[/tex]
Hence, the mean of road accidents in December is 9.3
