jonathankingsberry52
22.09.2020 •
Mathematics
The wholesale price for a shirt is $6.50. A certain department store marks up the wholesale price by 60% . Find the price of the shirt in the department store. Round your answer to the nearest cent, as necessary.
Solved
Show answers
More tips
- H Health and Medicine Boosting Immunity: A Complete Guide on How to Improve Your Body’s Natural Defenses...
- C Computers and Internet The Best Antivirus Programs for your PC...
- H Health and Medicine Angina: Causes, Symptoms, and Treatment...
- C Computers and Internet How to Learn to Type Fast?...
- F Food and Cooking Delight for Gourmets: How to Prepare Liver Pate...
- S Style and Beauty How to braid friendship bracelets?...
- H Health and Medicine Mercury Thermometer Danger: What to do when a thermometer breaks?...
- F Food and Cooking Which Calamari Salad is the Most Delicious?...
- S Society and Politics 10 Tips for Boosting Your Self-Esteem...
- F Food and Cooking The Most Delicious and Simple Fish in Batter Recipe...
Answers on questions: Mathematics
- M Mathematics Someone help me please...
- M Mathematics A food pantry is making packages. Each package weighs 82 pounds. Here are a situation. For the situation, write an equation to represent the situation. If you get stuck,...
- M Mathematics Simplify. [7 (2+3)] -2 O A.33 O B.21 O C. 12 O D.15...
- M Mathematics As a block of ice melts, its weight changes from lb to 2 1/2 lb to 1/2/b. This change takes 1/2hr.The ice melts at a constant rate. At what ratedoes the weight of the...
- M Mathematics Mr. Verrengia buys 6 water bottles for $1.99. How much does 1 water bottle cost?...
- M Mathematics Pick one also 12+2-3+8=?...
- M Mathematics Nathan is using his grandmother recipe to make pies on Monday he used 15 3/4 cups of sugar to make 9 pies on Tuesday he used 22 3/4 cups of sugar to make 13 pies...
- M Mathematics What is the qoutient of 0.1 and 20...
- M Mathematics Ramrio walks into a store that advetises a sale of 30% off everything in the store He writes the following expression to caculate the sale price...
- M Mathematics Why is it important to simplify radical expressions before adding or subtracting them?...
Ответ:
Sample variance = 228.408
Standard deviation = 15.113
Step-by-step explanation:The well formatted frequency table has been attached to this response.
To calculate the sample variance and standard deviation of the given grouped data, follow these steps:
i. Find the midpoint (m) of the class interval.
This is done by adding the lower bounds and upper bounds of the class intervals and dividing the result by 2. i.e
For class 0 - 9, we have
m = (0 + 9) / 2 = 4.5
For class 10 - 19, we have
m = (10 + 19) / 2 = 14.5
For class 20 - 29, we have
m = (20 + 29) / 2 = 24.5
For class 30 - 39, we have
m = (30 + 39) / 2 = 34.5
For class 40 - 49, we have
m = (40 + 49) / 2 = 44.5
This is shown in the third column of the attached table.
ii. Find the product of each of the frequencies of the class intervals and their corresponding midpoints. i.e
For class 0 - 9, we have
frequency (f) = 13
midpoint (m) = 4.5
=> f x m = 13 x 4.5 = 58.5
For class 10 - 19, we have
frequency (f) = 7
midpoint (m) = 14.5
=> f x m = 7 x 14.5 = 101.5
For class 20 - 29, we have
frequency (f) = 10
midpoint (m) = 24.5
=> f x m = 10 x 24.5 = 245
For class 30 - 39, we have
frequency (f) = 9
midpoint (m) = 34.5
=> f x m = 9 x 34.5 = 310.5
For class 40 - 49, we have
frequency (f) = 11
midpoint (m) = 44.5
=> f x m = 11 x 44.5 = 489.5
This is shown in the fourth column of the attached table.
iii. Calculate the mean (x) of the distribution i.e
This is done by finding the sum of all the results in (ii) above and dividing the outcome by the sum of the frequencies. i.e
x = ∑(f x m) ÷ ∑f
Where;
∑(f x m) = 58.5 + 101.5 + 245 + 310.5 + 489.5 = 1205
∑f = 13 + 7 + 10 + 9 + 11 = 50
=> x = 1205 ÷ 50
=> x = 24.1
Therefore, the mean is 24.1
This is shown on the fifth column of the attached table.
iv. Calculate the deviation of the midpoints from the mean.
This is done by finding the difference between the midpoints and the mean. i.e m - x where x = mean = 24.1 and m = midpoint
For class 0 - 9, we have
midpoint (m) = 4.5
=> m - x = 4.5 - 24.1 = -19.6
For class 10 - 19, we have
midpoint (m) = 14.5
=> m - x = 14.5 - 24.1 = -9.6
For class 20 - 29, we have
midpoint (m) = 24.5
=> m - x = 24.5 - 24.1 = 0.4
For class 30 - 39, we have
midpoint (m) = 34.5
=> m - x = 34.5 - 24.1 = 10.4
For class 40 - 49, we have
midpoint (m) = 44.5
=> m - x = 44.5 - 24.1 = 20.4
This is shown on the sixth column of the attached table.
v. Find the square of each of the results in (iv) above.
This is done by finding (m-x)²
For class 0 - 9, we have
=> (m - x)² = (-19.6)² = 384.16
For class 10 - 19, we have
=> (m - x)² = (-9.6)² = 92.16
For class 20 - 29, we have
=> (m - x)² = (0.4)² = 0.16
For class 30 - 39, we have
=> (m - x)² = (10.4)² = 108.16
For class 40 - 49, we have
=> (m - x)² = (20.4)² = 416.16
This is shown on the seventh column of the attached table.
vi. Multiply each of the results in (v) above by their corresponding frequencies.
This is done by finding f(m-x)²
For class 0 - 9, we have
=> f(m - x)² = 13 x 384.16 = 4994.08
For class 10 - 19, we have
=> f(m - x)² = 7 x 92.16 = 645.12
For class 20 - 29, we have
=> f(m - x)² = 10 x 0.16 = 1.6
For class 30 - 39, we have
=> f(m - x)² = 9 x 108.16 = 973.44
For class 40 - 49, we have
=> f(m - x)² = 11 x 416.16 = 4577.76
This is shown on the eighth column of the attached table.
vi. Calculate the sample variance.
Variance σ², is calculated by using the following relation;
σ² = ∑f(m-x)² ÷ (∑f - 1)
This means the variance is found by finding the sum of the results in (vi) above and then dividing the result by one less than the sum of all the frequencies.
∑f(m-x)² = sum of the results in (vi)
∑f(m-x)² = 4994.08 + 645.12 + 1.6 + 973.44 + 4577.76 = 11192
∑f - 1 = 50 - 1 = 49 {Remember that ∑f was calculated in (iii) above}
∴ σ² = 11192 ÷ 49 = 228.408
Therefore, the variance is 228.408
vii. Calculate the standard deviation
Standard deviation σ, is calculated by using the following relation;
σ =√ [ ∑f(m-x)² ÷ (∑f - 1) ]
This is done by taking the square root of the variance calculated above.
σ =
σ = 15.113
Therefore, the standard deviation is 15.113