Question

controls and variables
date:
i. write a definition for each of the following words in your own words. yes look them up but dont copy!

• control -
• variable -
• independent variable -
• dependent variable -

ii. spongebob and his bikini bottom pals have been busy doing a little research. read the following description for each of their experiments and answer the questions provided.
krusty krabs breath mints
mr. krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people get from eating crabby patties at the krusty krab. he asked 100 customers with a history of bad breath to try his new breath mint. he had 50 customers (group a) eat a breath mint after they finished eating a crabby patty. the other 50 customers (group b) also received a breath mint after they finished the sandwich, however, it was just a regular breath mint and did not have the secret ingredient. both groups were told that they were getting the breath mint that would cure their bad breath two hours after eating the crabby patties, 30 customers in group a and 10 customers in group b reported having better breath than they normally had after eating crabby patties.

1. which group of people were in the control group?
2. what is the independent variable?
3. what is the dependent variable?
4. what do you think mr. krabs’ conclusion should be?
5. give examples/details that support why you think in#4 what mr. krabs’ conclusion should be.

Explanation:

1. The control group is the one that doesn't receive the treatment being tested. Group B had a regular breath - mint, so they are the control group.
2. The independent variable is what is changed or manipulated in an experiment. Here, Mr. Krabs is changing the type of breath - mint (secret ingredient or regular), so the type of breath - mint is the independent variable.
3. The dependent variable is what is measured or observed. In this case, it's the improvement in bad breath, as that's what is being noted in the customers.
4. Mr. Krabs should conclude that the breath - mint with the secret ingredient is effective in improving bad breath compared to the regular breath - mint, since more people in Group A (30) reported better breath than in Group B (10).
5. The data shows that 30 out of 50 in Group A (with the secret - ingredient breath - mint) reported better breath, while only 10 out of 50 in Group B (with regular breath - mint) did. This difference in the number of customers reporting better breath supports the conclusion that the secret - ingredient breath - mint is effective.

Answer:

1. Group B
2. Type of breath - mint
3. Improvement in bad breath
4. The breath - mint with the secret ingredient is effective in improving bad breath compared to the regular breath - mint.
5. 30 out of 50 in Group A reported better breath while only 10 out of 50 in Group B did.