Use this data for #1,2,3

Student Group A: 56, 14, 26, 28, 29, 45, 32, 80, 3, 10

Student Group B: 27, 24, 18, 19, 5, 16, 22, 10, 6, 20

Find mean of group A and B (round to tenth) and THEN find their difference
Find range of each student group and tell which group is more inconsistent
Find the median of each student group, and find their difference in medians
A large company wants to find the favorite animal of their employees…would surveying every 5th woman who uses the copier, be a random, representative sample? Explain your answer.
50 students are randomly selected and 4 own cats. If there are 800 students, use a proportion to estimate how many of them own cats?

1 answer

1. Mean of Group A and Group B

Group A: The numbers are: 56, 14, 26, 28, 29, 45, 32, 80, 3, 10.

To find the mean: \[ \text{Mean A} = \frac{\text{Sum of Group A}}{\text{Count of Group A}} = \frac{56 + 14 + 26 + 28 + 29 + 45 + 32 + 80 + 3 + 10}{10} = \frac{ 56 + 14 + 26 + 28 + 29 + 45 + 32 + 80 + 3 + 10 }{ 10 } = \frac{ 302 }{ 10 } = 30.2 \]

Group B: The numbers are: 27, 24, 18, 19, 5, 16, 22, 10, 6, 20.

To find the mean: \[ \text{Mean B} = \frac{\text{Sum of Group B}}{\text{Count of Group B}} = \frac{27 + 24 + 18 + 19 + 5 + 16 + 22 + 10 + 6 + 20}{10} = \frac{ 27 + 24 + 18 + 19 + 5 + 16 + 22 + 10 + 6 + 20 }{ 10 } = \frac{ 147 }{ 10 } = 14.7 \]

Difference in Means: \[ \text{Difference} = \text{Mean A} - \text{Mean B} = 30.2 - 14.7 = 15.5 \]


2. Range of Each Student Group

Group A: Max = 80, Min = 3 \[ \text{Range A} = \text{Max} - \text{Min} = 80 - 3 = 77 \]

Group B: Max = 27, Min = 5 \[ \text{Range B} = \text{Max} - \text{Min} = 27 - 5 = 22 \]

Inconsistency Comparison: Group A has a larger range (77), indicating it is more inconsistent compared to Group B (22).


3. Median of Each Student Group

Group A: Sorted: 3, 10, 14, 26, 28, 29, 32, 45, 56, 80. Since there is an even number of values (10), the median is the average of the 5th and 6th values. Median A = (28 + 29) / 2 = 28.5

Group B: Sorted: 5, 6, 10, 16, 18, 19, 20, 22, 24, 27. Median B = (18 + 19) / 2 = 18.5

Difference in Medians: \[ \text{Difference in Medians} = \text{Median A} - \text{Median B} = 28.5 - 18.5 = 10.0 \]


4. Surveying Every 5th Woman Using the Copier

No, surveying every 5th woman who uses the copier is not a random, representative sample. This is because the sample is biased toward women who use the copier, which may not be representative of all women in the company. It may exclude women who do not use the copier or only those who happen to use it at certain times, leading to skewed results.


5. Estimate of Students Owning Cats

Using the proportion of students who own cats: \[ \text{Fraction of Students Owning Cats} = \frac{4}{50} \]

To estimate the total number of students owning cats among 800 students: \[ \text{Estimated Number of Cat Owners} = \frac{4}{50} \times 800 = 64 \]

Therefore, it is estimated that 64 students own cats.