A, B, Care three sets of values of x: A: 2, 3, 7, 1, 3, 2, 3,
B: 7, 5, 9, 12, 5, 3, 8,
C: 4, 4, 11, 7, 2, 3, 4
Find the difference between A's & B's mean

Options

A. 3
B. 4
C. 5
D. 2

Answer

To find the difference between the means of sets A and B, we will follow these steps:

### Step 1: Calculate the Mean of Set A
1. **List the values in Set A**: A = {2, 3, 7, 1, 3, 2, 3}
2. **Sum the values**:
\[ 2 + 3 + 7 + 1 + 3 + 2 + 3 = 21 \]
3. **Count the number of observations**: There are 7 values in Set A.
4. **Calculate the mean**:
\[ \text{Mean of A} = \frac{\text{Sum of A}}{\text{Number of observations in A}} = \frac{21}{7} = 3 \]

### Step 2: Calculate the Mean of Set B
1. **List the values in Set B**: B = {7, 5, 9, 12, 5, 3, 8}
2. **Sum the values**:
\[ 7 + 5 + 9 + 12 + 5 + 3 + 8 = 49 \]
3. **Count the number of observations**: There are 7 values in Set B.
4. **Calculate the mean**:
\[ \text{Mean of B} = \frac{\text{Sum of B}}{\text{Number of observations in B}} = \frac{49}{7} = 7 \]

### Step 3: Find the Difference Between the Means
1. **Calculate the difference**:
\[ \text{Difference} = \text{Mean of B} - \text{Mean of A} = 7 - 3 = 4 \]

### Final Answer
The difference between the mean of A and the mean of B is **4**.

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