To find the updated sample average after including a new data point, you need to use the formula for calculating the sample average:
\[ \text{New average} = \frac{( \text{Old average} \times \text{Number of data points}) + \text{New data point}}{\text{Number of data points} + 1} \]
Given:
Old average = 40
Number of data points = 50
New data point = 142
Let's substitute these values into the formula:
\[ \text{New average} = \frac{(40 \times 50) + 142}{50 + 1} \]
\[ = \frac{(2000 + 142)}{51} \]
\[ = \frac{2142}{51} \]
\[ \approx 42 \]
Therefore, the updated sample average after including the new data point is approximately 42.