Original Project
Control of Variables
If more than one variable changes at the same time in an experiment, the outcome of the experiment may not be cl…
Item CR013003: To find out if the type of swimsuit swimmers wear affects a swim team's performance, it is important that everyone wear the same kind of swim cap because otherwise it wouldn't be possible to find out the effect of the swimsuits on the team's performance.
A swim team thinks that the swimsuits and swim caps they use may affect the team's performance.
The swim team decides to test if the swimsuits make a difference on how fast they can swim.
They split the team in two groups. The two groups wear different kinds of swimsuits and the same kind of swim caps.
Why is it important that both groups wear the same kind of swim caps?
- By wearing the same kind of swim caps they can learn about the effect of the swim caps and the effect of the swimsuits.
- By wearing the same kind of swim caps they can learn about the effect of the swim caps.
- If they do not wear the same kind of swim caps they cannot learn about the effect of the swimsuits.
- It is NOT important to wear the same kind of swim caps because they are not testing the effect of the swim caps.
- Distribution of Responses
- Students Responding Correctly
| Group | Correct | Total | Percent |
|---|---|---|---|
| Overall | 1498 | 2682 | 56% |
| Grades | |||
| 6–8 | 731 | 1505 | 49% |
| 9–12 | 759 | 1163 | 65% |
| Gender | |||
| Male | 693 | 1319 | 53% |
| Female | 791 | 1339 | 59% |
| Primary Language | |||
| English | 1329 | 2261 | 59% |
| Other | 147 | 378 | 39% |