1. **Problem Statement:** Find the range, variance, and standard deviation of the net worth data (in billions): 59, 52, 28, 26, 19, 19, 18, 17, 17, 17.
2. **Range:** The range is the difference between the maximum and minimum values.
$$\text{Range} = 59 - 17 = 42$$
3. **Variance and Standard Deviation:** Use the formulas:
$$\text{Mean} = \frac{\sum x_i}{n}$$
$$\text{Variance} = \frac{\sum (x_i - \bar{x})^2}{n}$$
$$\text{Standard Deviation} = \sqrt{\text{Variance}}$$
4. Calculate the mean:
$$\bar{x} = \frac{59 + 52 + 28 + 26 + 19 + 19 + 18 + 17 + 17 + 17}{10} = \frac{272}{10} = 27.2$$
5. Calculate each squared deviation:
$$(59 - 27.2)^2 = 31.8^2 = 1011.24$$
$$(52 - 27.2)^2 = 24.8^2 = 615.04$$
$$(28 - 27.2)^2 = 0.8^2 = 0.64$$
$$(26 - 27.2)^2 = (-1.2)^2 = 1.44$$
$$(19 - 27.2)^2 = (-8.2)^2 = 67.24$$
$$(19 - 27.2)^2 = 67.24$$
$$(18 - 27.2)^2 = (-9.2)^2 = 84.64$$
$$(17 - 27.2)^2 = (-10.2)^2 = 104.04$$
$$(17 - 27.2)^2 = 104.04$$
$$(17 - 27.2)^2 = 104.04$$
6. Sum the squared deviations:
$$1011.24 + 615.04 + 0.64 + 1.44 + 67.24 + 67.24 + 84.64 + 104.04 + 104.04 + 104.04 = 2159.6$$
7. Calculate variance:
$$\text{Variance} = \frac{2159.6}{10} = 215.96$$
8. Calculate standard deviation:
$$\text{Standard Deviation} = \sqrt{215.96} \approx 14.7$$
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1. **Problem Statement:** Find the variance and standard deviation for the inches of rain data with given frequency distribution and sums:
Given:
$$n = 25, \sum f x_m = 12225, \sum f x_m^2 = 329431$$
2. Calculate the mean:
$$\bar{x} = \frac{\sum f x_m}{n} = \frac{12225}{25} = 489$$
3. Calculate variance using formula:
$$\text{Variance} = \frac{\sum f x_m^2}{n} - \bar{x}^2 = \frac{329431}{25} - 489^2$$
4. Calculate each term:
$$\frac{329431}{25} = 13177.24$$
$$489^2 = 239121$$
5. Calculate variance:
$$13177.24 - 239121 = -225943.76$$
This negative variance is impossible, indicating a misinterpretation of the data.
6. Correct interpretation: The sum $\sum f x_m = 12225$ likely represents $\sum f x_m^2$ and $\sum f x_m^2 = 329431$ is $\sum f x_m^3$ or a misprint.
7. Using the given sums as:
$$\sum f x_m = 329431, \sum f x_m^2 = 12225$$
Calculate mean:
$$\bar{x} = \frac{329431}{25} = 13177.24$$
Calculate variance:
$$\text{Variance} = \frac{12225}{25} - (13177.24)^2 = 489 - 173654000 \approx -173653511$$
Still negative, so data likely misaligned.
8. Since the problem states $n=25$, $\sum f x_m = 12225$, and $\sum f x_m^2 = 329431$, use these:
$$\bar{x} = \frac{12225}{25} = 489$$
$$\text{Variance} = \frac{329431}{25} - 489^2 = 13177.24 - 239121 = -225943.76$$
Negative variance again.
9. Conclusion: The data for problem #5 is inconsistent or incorrectly transcribed, so variance and standard deviation cannot be reliably calculated.
**Final answers:**
- Problem #4 Range: 42
- Problem #4 Variance: 215.96
- Problem #4 Standard Deviation: 14.7
- Problem #5 Variance and Standard Deviation: Cannot be determined due to inconsistent data.
Net Worth Range Ae41Ea
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