Question

Sixty-five randomly selected car salespersons were asked the number of cars they generally sell in one week. Fourteen people answered that they generally sell three cars; seventeen generally sell four cars; thirteen generally sell five cars; eleven generally sell six cars; ten generally sell seven cars. Find the relative and cumulative frequency.

Answer 1

Relative frequency = frequency of the class total.

Cumulative relative frequency is the accumulation of the previous relative frequencies.

Let us write the given data, then find them

3 cars: 14

4 cars: 17

5 cars: 13

6 cars: 11

7 cars: 10

1. find the total number of cars by adding all numbers above

`\begin{gathered} T=14+17+13+11+10 \\ T=65 \end{gathered}`

2. divide each number by 65 to find the relative frequency

`\begin{gathered} 3\rightarrow(14)/(65) \\ 4\rightarrow(17)/(65) \\ 5\rightarrow(13)/(65) \\ 6\rightarrow(11)/(65) \\ 7\rightarrow(10)/(65) \end{gathered}`

3. To find the cumulative frequency add each fraction by the previous fraction

`\begin{gathered} 3\rightarrow(14)/(65) \\ 4\rightarrow(31)/(65) \\ 5\rightarrow(44)/(65) \\ 6\rightarrow(55)/(65) \\ 7\rightarrow(65)/(65)=1 \end{gathered}`