Let’s work through each scenario to identify the
independent and
dependent variables.
---
What are independent and dependent variables?
-
Independent variable: This is what you *change* or *control* in an experiment. It’s the cause.
-
Dependent variable: This is what you *measure* or *observe* as a result. It’s the effect.
Think of it like this:
> “I change X (independent), and I see how Y changes (dependent).”
---
## Scenario 1:
> A cow is given a growth hormone and then compared to another cow that was not given a growth hormone. Both cows were weighed at 2 years.
- What did they change? → Whether the cow got the growth hormone or not.
- What did they measure? → The weight of the cows after 2 years.
✔ Independent: Growth hormone (given or not)
✔ Dependent: Weight of the cow
---
## Scenario 2:
> Mosquito repellent is sprayed on one arm and the other arm is not sprayed. The number of mosquito bites is counted after 2 hours.
- What did they change? → Whether repellent was sprayed on the arm.
- What did they measure? → Number of mosquito bites.
✔ Independent: Repellent applied (yes/no)
✔ Dependent: Number of mosquito bites
---
## Scenario 3:
> One grape is placed in tap water and another grape is placed in salt water. The change in their mass is measured after a day.
- What did they change? → Type of water (tap vs. salt)
- What did they measure? → Change in mass of the grapes
✔ Independent: Type of water (tap or salt)
✔ Dependent: Change in mass of the grape
---
All reasoning done. Now, final answer:
Final Answer:
Scenario 1: Independent = Growth hormone; Dependent = Cow’s weight
Scenario 2: Independent = Repellent application; Dependent = Number of mosquito bites
Scenario 3: Independent = Type of water; Dependent = Change in grape’s mass
Parent Tip: Review the logic above to help your child master the concept of independent vs dependent variable worksheet with answers.
