Question

Raul wants to study how pot size affects the growth of plants. To do this, he intends to purchase three different pots of varying diameter. Then, he will fill each pot with the same amount of soil and plant different kinds of flowers in each pot. Finally, he will place the pots side by side in a sunny location and water each pot daily with the same amount of water. Will Raul's experimental set-up produce valid results?

Answer 1

Answer: The answer position may vary. But the correct answer is D. No; Raul changes more than one variable so the results will be invalid.

Explanation:

Raul's experimental set-up will not produce valid results because he intends to change more than one variable.

One variable that Raul will change is the pot size. According to the description, however, Raul will also change one other variable—the type of flower that is planted. Even though Raul plans on using flowers only, he should use the same type of flower in each pot, not different types.

Valid results are only produced when only one variable is changed at a time.

Answer 2

No, Raul changes the more than one variable so the results will be invalid.