*How Long Do You Take To Get Ready In The Morning

To Go To School?*

By: Vanessa Miranda, Yesenia Flores, and Pedro Huerta

Period 62011-2012

California Standards: 8.0: Students organize and describe distributions of

data by using a number of different methods, including frequency tables, histograms, standard line and bar graphs, stem-and-leaf displays, scatter plots, and box-and-whisker plots.

17.0 Students determine confidence intervals for a simple random sample from a normal distribution of data and determines the sample size required for a desire margin of error.

18.0 Students determine the p-value for a statistic for a simple random sample from a normal distribution.

Hypothesis

We believe that the average minutes that students from Century High School take to get ready is 15 minutes.

Data Collection

We used Stratified Sampling to gather our information/data. We asked boys and girls from each grade at Century High School how long do they take to get ready for school. We asked 40 students, 5 boys and 5 girls from each grade.

Data

Time in minutes

45,50,60,1:30,1:15,20,30,25,30,30,30,30,30, 30,45,45,30,10,30,20,50,15,20,30,45,25,25,45,30,20,15,10,15,20,60,5,30,35,20,10,25

Histogram

12.05 26.2 40.4 54.55 68.7 82.9 97.05 111.20

5

10

15

20

25

How long do you take to get ready?

Number Of Minutes

num

ber

Of

Stud

ents

Statistics

From our survey, Students mean time to get ready is 31.625, with a sample standard deviation 18.095

Confidence Interval

95% Confidence Interval Z-Interval (26.017, 32.477) We are 95% confident mean

commute time for all students to get ready are between 26.017 to 32.477 minutes.

Hypothesis Testing Test Hypothesis We believe that the average minutes that

students from Century High School take to get ready is 15 minutes.

45,50,60,1:30,1:15,20,30,25,30,30,30,30,30, 30,45,45,30,10,30,20,50,15,20,30,45,25,25,45,30,20,15,10,15,20,60,5,30,35,20,10,25

At 5% level of significance, we failed to reject. There is enough evidence to support our claim.

Conclusion We hypothesized that century students time

in minutes to get ready was an average of 15 minutes. In our survey of 40 students, we find the sample mean of with a standard deviation of 18 minutes. We concluded that the population mean for all students is between 26.017 to 32.477 minutes with a 95% confident. We test our initial hypothesis with5% level of significance, and confirm our hypothesis is correct.

Error Analysis:

Our Sample mean is 18 minutes, and we are 95% confidence level for the population mean is between 26.017 to 32.477 minutes. The marginal error is about 6 minutes.

our sample error is due to possible under representation of the population. Some students might have had special occasions and that’s the reason they have to take more time to get ready. While other students were just lazy like Pedro Huerta. Some students might of lie on our survey and just might of said a round number that just came to their head.