Explore the Relationship Between Independent and Dependent Variables - Free Printable

Let's go through each scenario and identify the Independent Variable (IV) and Dependent Variable (DV).

Definitions:

- Independent Variable (IV): The variable that is deliberately changed or manipulated by the researcher.
- Dependent Variable (DV): The outcome or response that is measured to see if it is affected by the IV.

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1. Justin wants to determine the effect of fertilizer on the growth of grass.
- IV: Type or amount of fertilizer
- DV: Growth of grass

2. Randell wants to determine if salinity has an effect on his goldfish.
- IV: Salinity (salt concentration in water)
- DV: Health, behavior, or survival of goldfish (any measurable effect)

3. James wants to know the effect of studying an extra 10 minutes each day on his Biology grade.
- IV: Amount of study time (extra 10 minutes per day)
- DV: Biology grade

4. Joelle wants to determine the effect of pesticides on the size of the apples in the orchard.
- IV: Use or type of pesticide
- DV: Size of apples

5. Billy wants to know if increasing his exercise will decrease the time it takes him to run a kilometer.
- IV: Amount of exercise
- DV: Time to run a kilometer

6. Angel wants to know if the type of detergent has an effect on the cleanliness of her clothes.
- IV: Type of detergent
- DV: Cleanliness of clothes

7. Madison wants to determine if the weight of the dog will have an effect on the number of puppies in the litter.
- IV: Weight of the dog
- DV: Number of puppies in the litter

8. Zack wants to determine if the amount of time spent on social media has an effect on anxiety levels.
- IV: Amount of time spent on social media
- DV: Anxiety levels

9. Comer wants to determine if the diet of a rat has an effect on the rats overall health (weight, bone density).
- IV: Diet of the rat
- DV: Overall health (weight, bone density)

10. Allison wants to determine if the deer population in the area is influenced by the coyote population.
- IV: Coyote population
- DV: Deer population

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Final Answers:

| # | IV | DV |
|---|----|----|
| 1 | Fertilizer | Growth of grass |
| 2 | Salinity | Goldfish health/behavior/survival |
| 3 | Study time (extra 10 minutes/day) | Biology grade |
| 4 | Pesticides | Size of apples |
| 5 | Exercise amount | Time to run a kilometer |
| 6 | Type of detergent | Cleanliness of clothes |
| 7 | Weight of the dog | Number of puppies in the litter |
| 8 | Time spent on social media | Anxiety levels |
| 9 | Diet of the rat | Overall health (weight, bone density) |
| 10 | Coyote population | Deer population |

✔ These answers reflect how each experiment manipulates one factor (IV) to observe its effect on another (DV).