College

The marks obtained in the previous class test out of 20 were as follows:

[tex]\[
\begin{tabular}{|l|l|l|l|l|l|}
\hline
19 & 10 & 9 & 8 & 14 & 11 \\
\hline
11 & 11 & 12 & 11 & 9 & 12 \\
\hline
19 & 19 & 17 & 10 & 13 & 8 \\
\hline
18 & 16 & 17 & 5 & 14 & 16 \\
\hline
4 & 12 & 10 & 7 & 18 & 15 \\
\hline
\end{tabular}
\][/tex]

Make the class width 3 and the lower limit of the first class 2. With the given data, complete the following table:

[tex]\[
\begin{tabular}{|c|c|c|c|c|c|}
\hline
\begin{tabular}{l}
Intervals \\
Intervalle
\end{tabular}
& Class Midpoints Klasmiddelpunte
& \begin{tabular}{l}
Frequencies \\
Frekwensies
\end{tabular}
& Cumulative frequency/ Kumulatiewe frekwensies
& Relative Cumulative frequency/ Relatiewe Kumulatiewe frekwensies
& Relative frequency Relatiewe frekwensie \\
\hline
[ - ) & & & & G & \\
\hline
[ - ) & & C & E & & I \\
\hline
[ A - ) & B & & & & \\
\hline
[ - ) & & & & H & \\
\hline
[ - ) & & & F & & J \\
\hline
[ - ) & & D & & & \\
\hline
Total & & & & & \\
\hline
\end{tabular}
\][/tex]

What is the value of [tex]\(E\)[/tex] in the table?

A. 3
B. 18
C. 23
D. 10

Answer :

To solve this problem, we need to organize the given data into class intervals and calculate various frequencies. We are asked specifically to find the value of [tex]\( E \)[/tex], which is the cumulative frequency for a particular interval. Let's solve this step by step.

1. Understanding the Data:
- We have a list of marks ranging from 1 to 20.

2. Determine Intervals:
- The class width is 3.
- The lower limit of the first class is 2.
- With a class width of 3 starting from 2, our intervals would be:
- [tex]\([2, 5)\)[/tex]
- [tex]\([5, 8)\)[/tex]
- [tex]\([8, 11)\)[/tex]
- [tex]\([11, 14)\)[/tex]
- [tex]\([14, 17)\)[/tex]
- [tex]\([17, 20)\)[/tex]

3. Count Frequencies for Each Interval:
- Count how many marks fall into each of the intervals:
- [tex]\([2, 5)\)[/tex]: 1
- [tex]\([5, 8)\)[/tex]: 2
- [tex]\([8, 11)\)[/tex]: 8
- [tex]\([11, 14)\)[/tex]: 9
- [tex]\([14, 17)\)[/tex]: 4
- [tex]\([17, 20)\)[/tex]: 6

4. Calculate Cumulative Frequencies:
- The cumulative frequency is the sum of the frequencies up to the current interval:
- [tex]\([2, 5)\)[/tex]: 1
- [tex]\([5, 8)\)[/tex]: 3 (1 from previous interval + 2 from this)
- [tex]\([8, 11)\)[/tex]: 11 (3 from previous intervals + 8 from this)
- [tex]\([11, 14)\)[/tex]: 20 (11 from previous intervals + 9 from this)
- [tex]\([14, 17)\)[/tex]: 24 (20 from previous intervals + 4 from this)
- [tex]\([17, 20)\)[/tex]: 30 (24 from previous intervals + 6 from this)

5. Identify Target Interval for [tex]\( E \)[/tex]:
- We need the cumulative frequency for the interval [tex]\([5, 8)\)[/tex].

6. Result for [tex]\( E \)[/tex]:
- The cumulative frequency for the interval [tex]\([5, 8)\)[/tex] is [tex]\( 3 \)[/tex].

So, the value of [tex]\( E \)[/tex] is 3.