Categorical Data
Grade 11 · Statistics · Worksheet 2
- A medical researcher is studying the effectiveness of a new drug for reducing cholesterol levels. In a clinical trial with 180 patients, the mean reduction in LDL cholesterol was 28.4 mg/dL with a standard deviation of 7.2 mg/dL. The researcher wants to test if this reduction is significantly greater than the standard treatment's average reduction of 25 mg/dL. Using a significance level of α = 0.01, calculate the test statistic and determine whether there is sufficient evidence to support the claim that the new drug provides a greater reduction than the standard treatment.
- A. z = 4.24, Reject H₀
- B. z = 2.12, Fail to reject H₀
- C. z = 6.36, Reject H₀
- D. z = 3.18, Fail to reject H₀
- A circle is inscribed in a right triangle with legs measuring 8 cm and 15 cm. The circle is tangent to all three sides of the triangle. What is the radius of the inscribed circle? Answer: ______________
- Hana surveyed 36 students about their preferred learning method: 14 prefer visual, 12 prefer auditory, 10 prefer kinesthetic. Create a frequency table summarizing this categorical data. Answer: ______________
- Isabella surveyed 27 students about their favorite subject. The results were: 12 Math, 7 Science, 2 History, 6 English. Create a frequency table showing the counts for each subject. Answer: ______________
- Isabella surveyed 72 students about their favorite subject and preferred learning style. The results showed: 17 students like Math and Visual, 12 like Math and Auditory, 22 like Science and Visual, 7 like Science and Auditory, 9 like English and Visual, and 5 like English and Auditory. Create a two-way frequency table summarizing this categorical data. Answer: ______________
- Aroha surveyed 63 students about their preferred learning environment. 21 preferred classroom, 17 preferred online, 13 preferred hybrid, and 12 preferred outdoor. Create a frequency table summarizing this categorical data. Answer: ______________
- Emma surveyed students about their favorite subject: Math: 17, Science: 13, English: 9, History: 11. Create a frequency table summarizing the data. Answer: ______________
Answer Key & Explanations
Categorical Data · Grade 11 · Worksheet 2
- A medical researcher is studying the effectiveness of a new drug for reducing cholesterol levels. In a clinical trial with 180 patients, the mean reduction in LDL cholesterol was 28.4 mg/dL with a standard deviation of 7.2 mg/dL. The researcher wants to test if this reduction is significantly greater than the standard treatment's average reduction of 25 mg/dL. Using a significance level of α = 0.01, calculate the test statistic and determine whether there is sufficient evidence to support the claim that the new drug provides a greater reduction than the standard treatment. Answer: C. z = 6.36, Reject H₀ Solution: H₀: μ ≤ 25 mg/dL (new drug is not better than standard treatment) H₁: μ > 25 mg/dL (new drug provides greater reduction) z = (x̄ - μ) / (σ/√n) z = (28.4 - 25) / (7.2/√180) z = 3.4 / (7.2/13.4164) z = 3.4 / 0.5367 z = 6.36 For α = 0.01 in a right-tailed test, the critical z-value is 2.33 Since…
Full step-by-step solution
Step 1: State the hypotheses
H₀: μ ≤ 25 mg/dL (new drug is not better than standard treatment)
H₁: μ > 25 mg/dL (new drug provides greater reduction)
Step 2: Calculate the test statistic
z = (x̄ - μ) / (σ/√n)
z = (28.4 - 25) / (7.2/√180)
z = 3.4 / (7.2/13.4164)
z = 3.4 / 0.5367
z = 6.36
Step 3: Determine the critical value
For α = 0.01 in a right-tailed test, the critical z-value is 2.33
Step 4: Make a decision
Since 6.36 > 2.33, we reject the null hypothesis
Step 5: State the conclusion
There is sufficient evidence at the 0.01 significance level to support the claim that the new drug provides a greater reduction in LDL cholesterol than the standard treatment.
The correct answer is z = 6.36, Reject H₀.
- A circle is inscribed in a right triangle with legs measuring 8 cm and 15 cm. The circle is tangent to all three sides of the triangle. What is the radius of the inscribed circle? Answer: 3 Solution: Calculate the hypotenuse of the right triangle using the Pythagorean theorem. Hypotenuse = sqrt(8^2 + 15^2) = sqrt(64 + 225) = sqrt(289) = 17 cm. Calculate the semiperimeter (s) of the triangle.
Full step-by-step solution
Step 1: Calculate the hypotenuse of the right triangle using the Pythagorean theorem.
Hypotenuse = sqrt(8^2 + 15^2) = sqrt(64 + 225) = sqrt(289) = 17 cm.
Step 2: Calculate the semiperimeter (s) of the triangle.
s = (8 + 15 + 17) / 2 = 40 / 2 = 20 cm.
Step 3: Calculate the area (A) of the triangle.
A = (1/2) * leg1 * leg2 = (1/2) * 8 * 15 = 60 cm².
Step 4: Use the formula for the inradius (r) of a triangle: r = A / s.
r = 60 / 20 = 3 cm.
The radius of the inscribed circle is 3 cm.
- Hana surveyed 36 students about their preferred learning method: 14 prefer visual, 12 prefer auditory, 10 prefer kinesthetic. Create a frequency table summarizing this categorical data. Answer: Visual: 14, Auditory: 12, Kinesthetic: 10, Total: 36 Solution: Identify the categories: Visual, Auditory, Kinesthetic Record the frequency for each category: Visual = 14, Auditory = 12, Kinesthetic = 10 Calculate the total: 14 + 12 + 10 = 36 Visual | 14 Auditory | 12 Kinesthetic | 10 Total | 36
Full step-by-step solution
Step 1: Identify the categories: Visual, Auditory, Kinesthetic
Step 2: Record the frequency for each category: Visual = 14, Auditory = 12, Kinesthetic = 10
Step 3: Calculate the total: 14 + 12 + 10 = 36
Step 4: Construct the frequency table:
Preferred Learning Method | Frequency
Visual | 14
Auditory | 12
Kinesthetic | 10
Total | 36
- Isabella surveyed 27 students about their favorite subject. The results were: 12 Math, 7 Science, 2 History, 6 English. Create a frequency table showing the counts for each subject. Answer: Math: 12, Science: 7, History: 2, English: 6 Solution: Step 1: Identify the categories: Math, Science, History, English Step 2: Record the count for each category from the survey data Step 3: Math: 12 students Step 4: Science: 7 students Step 5: History: 2 students Step 6: English: 6 students Step 7: Verify the total: 12 + 7 + 2 + 6 = 27 students…
Full step-by-step solution
Step 1: Identify the categories: Math, Science, History, English
Step 2: Record the count for each category from the survey data
Step 3: Math: 12 students
Step 4: Science: 7 students
Step 5: History: 2 students
Step 6: English: 6 students
Step 7: Verify the total: 12 + 7 + 2 + 6 = 27 students
The frequency table shows: Math: 12, Science: 7, History: 2, English: 6
- Isabella surveyed 72 students about their favorite subject and preferred learning style. The results showed: 17 students like Math and Visual, 12 like Math and Auditory, 22 like Science and Visual, 7 like Science and Auditory, 9 like English and Visual, and 5 like English and Auditory. Create a two-way frequency table summarizing this categorical data. Answer: 72 Solution: Set up the two-way table structure with Subjects (Math, Science, English) as rows and Learning Styles (Visual, Auditory) as columns, plus row and column totals. - Math & Visual: 17 - Math & Auditory: 12 - Science & Visual: 22 - Science & Auditory: 7 - English & Visual: 9 - English & Auditory: 5…
Full step-by-step solution
Step 1: Set up the two-way table structure with Subjects (Math, Science, English) as rows and Learning Styles (Visual, Auditory) as columns, plus row and column totals.
Step 2: Fill in the given frequencies:
- Math & Visual: 17
- Math & Auditory: 12
- Science & Visual: 22
- Science & Auditory: 7
- English & Visual: 9
- English & Auditory: 5
Step 3: Calculate row totals:
- Math total: 17 + 12 = 29
- Science total: 22 + 7 = 29
- English total: 9 + 5 = 14
Step 4: Calculate column totals:
- Visual total: 17 + 22 + 9 = 48
- Auditory total: 12 + 7 + 5 = 24
Step 5: Calculate grand total from row totals: 29 + 29 + 14 = 72
Or from column totals: 48 + 24 = 72
The completed two-way frequency table is:
Visual Auditory Total
Math 17 12 29
Science 22 7 29
English 9 5 14
Total 48 24 72
The grand total is 72 students.
- Aroha surveyed 63 students about their preferred learning environment. 21 preferred classroom, 17 preferred online, 13 preferred hybrid, and 12 preferred outdoor. Create a frequency table summarizing this categorical data. Answer: Classroom: 21, Online: 17, Hybrid: 13, Outdoor: 12 Solution: List all categories: Classroom, Online, Hybrid, Outdoor. Classroom: 21 Online: 17 Hybrid: 13 Outdoor: 12
Full step-by-step solution
Step 1: List all categories: Classroom, Online, Hybrid, Outdoor.
Step 2: Record the frequency for each category:
- Classroom: 21 students
- Online: 17 students
- Hybrid: 13 students
- Outdoor: 12 students
Step 3: Verify the total: 21 + 17 + 13 + 12 = 63 students.
Step 4: The completed frequency table is:
Classroom: 21
Online: 17
Hybrid: 13
Outdoor: 12
- Emma surveyed students about their favorite subject: Math: 17, Science: 13, English: 9, History: 11. Create a frequency table summarizing the data. Answer: Math: 17, Science: 13, English: 9, History: 11 Solution: Identify the categories: Math, Science, English, History. List the corresponding frequencies: 17, 13, 9, 11.
Full step-by-step solution
Step 1: Identify the categories: Math, Science, English, History.
Step 2: List the corresponding frequencies: 17, 13, 9, 11.
Step 3: Construct the frequency table:
| Subject | Frequency |
|----------|-----------|
| Math | 17 |
| Science | 13 |
| English | 9 |
| History | 11 |
The summarized data is Math: 17, Science: 13, English: 9, History: 11.