The mean of the data 1, 2, 10, 18, 3, 17, 19, is
A. 7
B. 10
C. 17
D. 70

Options

A. D
B. B
C. A
D. C

Answer

To find the mean of the data set 1, 2, 10, 18, 3, 17, 19, we can follow these steps:

### Step 1: Write down the data
The data set is:
1, 2, 10, 18, 3, 17, 19

### Step 2: Calculate the sum of the data
We need to add all the numbers together:
1 + 2 + 10 + 18 + 3 + 17 + 19

Calculating this step-by-step:
- 1 + 2 = 3
- 3 + 10 = 13
- 13 + 18 = 31
- 31 + 3 = 34
- 34 + 17 = 51
- 51 + 19 = 70

So, the total sum is 70.

### Step 3: Count the number of terms
Next, we count how many numbers are in the data set:
There are 7 numbers: 1, 2, 10, 18, 3, 17, 19

### Step 4: Calculate the mean
The formula for the mean is:
\[ \text{Mean} = \frac{\text{Sum of terms}}{\text{Number of terms}} \]
Substituting the values we found:
\[ \text{Mean} = \frac{70}{7} \]

### Step 5: Perform the division
Now, we divide 70 by 7:
\[ 70 \div 7 = 10 \]

### Conclusion
The mean of the data set is 10.

### Answer
The correct option is B. 10.

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