Sure! Let's complete the cumulative frequency table step by step.
We'll start with the given data and fill in the missing parts:
1. For the class mark "0-10":
- Frequency: 3
- Less than type Frequency: 3 (This is directly given)
2. For the class mark "10-20":
- Frequency: 15
- Less than type Frequency: We know the previous cumulative frequency is 3.
[tex]\[
\text{Cumulative Frequency} = 3 + 15 = 18
\][/tex]
So, the less than type Frequency is 18.
3. For the class mark "20-30":
- Frequency: 20
- Less than type Frequency: We know the previous cumulative frequency is 18.
[tex]\[
\text{Cumulative Frequency} = 18 + 20 = 38
\][/tex]
So, the less than type Frequency is 38.
4. For the class mark "30-40":
- Frequency: 12
- Less than type Frequency: We know the previous cumulative frequency is 38.
[tex]\[
\text{Cumulative Frequency} = 38 + 12 = 50
\][/tex]
So, the less than type Frequency is 50.
Finally, we sum up all the frequencies to get the total frequency \( N \):
[tex]\[
N = 3 + 15 + 20 + 12 = 50
\][/tex]
Here is the completed table:
[tex]\[
\begin{array}{|c|c|c|}
\hline
\text{Class mark} & \text{Frequency} & \text{Less than type Frequency} \\
\hline
0-10 & 3 & 3 \\
10-20 & 15 & 18 \\
20-30 & 20 & 38 \\
30-40 & 12 & 50 \\
\hline
\text{Total} & N=50 & \\
\hline
\end{array}
\][/tex]
