Unicellular organisms, such as bacteria, are responsible for causing illness in humans. Alana is studying unicellular organisms of bacteria present on a person's hands. She designs an experiment to test this. Students who washed their hands for 20 seconds had 50%, 56% and 51% of bacteria remaining on their hands; students who washed their hands for 40 seconds had 28% 25% and 26% of bacteria remaining on their hands; and students who washed their hands for 60 seconds had 18% 14% and 16% of bacteria remaining on their hands.
Alana's experiment suggests that the duration of hand washing has an impact on the amount of bacteria remaining on a person's hands. The results indicate that as the duration of hand washing increases, the percentage of bacteria remaining decreases. This implies that washing hands for a longer period of time is more effective at reducing the amount of bacteria present on the hands.
To test the effectiveness of handwashing in reducing the amount of bacteria on a person's hands, Alana designed an experiment. She measured the percentage of bacteria remaining on the hands of students who washed their hands for different time durations.
Here are the results of the experiment:
1. Students who washed their hands for 20 seconds had 50%, 56%, and 51% of bacteria remaining on their hands.
2. Students who washed their hands for 40 seconds had 28%, 25%, and 26% of bacteria remaining on their hands.
3. Students who washed their hands for 60 seconds had 18%, 14%, and 16% of bacteria remaining on their hands.
By comparing the percentages of bacteria remaining after different durations of handwashing, Alana can analyze the data to understand the relationship between duration and effectiveness of handwashing in reducing bacteria. From the results, it appears that longer durations of handwashing lead to lower percentages of bacteria remaining on the hands.
To summarize, Alana conducted an experiment to test the impact of handwashing duration on the reduction of bacteria on the hands. The results showed that longer durations of handwashing resulted in lower percentages of bacteria remaining on the hands.
To test the effectiveness of handwashing in reducing bacteria, Alana designed an experiment with different durations of handwashing and measured the percentage of bacteria remaining on students' hands after each duration. Here are the steps she followed:
1. Gather a group of students who will participate in the experiment.
2. Divide the students into three groups, each representing a different handwashing duration: 20 seconds, 40 seconds, and 60 seconds.
3. Instruct the first group to wash their hands for 20 seconds with soap and water.
4. After handwashing, use a bacterial swab to collect a sample from each student's hands.
5. Transfer the bacterial sample onto a culture medium or testing plate for bacteria growth.
6. Incubate the culture medium plates according to the appropriate conditions required for bacterial growth.
7. Once the bacterial colonies have grown, count the number of colonies on each plate.
8. Calculate the percentage of bacteria remaining by comparing the number of colonies on each plate to the total number of colonies after no handwashing was done.
9. Repeat steps 3-8 for the second and third group, who wash their hands for 40 seconds and 60 seconds, respectively.
10. Record the percentage of bacteria remaining for each group in a data table.
11. Analyze the data by comparing the percentages of bacteria remaining for each handwashing duration.
12. Draw conclusions based on the results of the experiment.
Note: It is important to note that this is a simplified explanation of the experiment. In actual practice, proper controls, replicates, and statistical analysis would be employed to ensure accurate and reliable results.
what is the Iv and Dv
In this experiment, the independent variable (IV) is the duration of handwashing. The researcher manipulated this variable by assigning different time durations (20 seconds, 40 seconds, and 60 seconds) to the three groups of students.
The dependent variable (DV) is the percentage of bacteria remaining on the students' hands after handwashing. This variable was measured and recorded as the outcome or response variable in the experiment.
what are the levels of IV and number of trials
In this experiment, the independent variable (IV) is the duration of handwashing, and there are three levels of this variable: 20 seconds, 40 seconds, and 60 seconds. These levels represent the different durations of handwashing that were tested.
The number of trials would depend on the number of participants included in the experiment. In the given scenario, the experiment involved groups of students. It does not specify the number of students in each group or if these groups were considered as individual trials. Therefore, it is not possible to provide an exact number of trials without more information.
what will be the mean for 50, 56 and 51
To calculate the mean (average) for the numbers 50, 56, and 51, you need to add them together and then divide the sum by the total number of values.
Mean = (50 + 56 + 51) / 3 = 157 / 3 = 52.333
Therefore, the mean of the numbers 50, 56, and 51 is approximately 52.333.