Question

post test: tools of inquiry
three students test the effect of fertilizer on bean plant growth. each student conducts one trial. they plant 10 bean seeds in each of three large pots of soil with different amounts of fertilizer. after two weeks, they measure the heights of the plants in each pot. then they find the average height for each amount of fertilizer. the table summarizes the results of the experiment.
effect of fertilizer on height of bean plants

amount of fertilizer	average height after 2 weeks (cm)
none	18.9	21.5	40.2
a little	19.5	32.7	39.7
a lot	34.3	33.2	16.5

which statement describes a pattern shown in the data?
o a. the data from trial 1 are inconsistent with the data from trials 2 and 3.
o b. the data for the average heights of the plants in all three trials contain errors.
o c. the trend in the data for trial 1 shows that plants grow taller if given more fertilizer.
o d. the trend in the data for trial 2 shows that more fertilizer causes less growth.

Explanation:

1. Analyze option A: The data from trial 1 is not inconsistent with trials 2 and 3 across - the - board. There is no clear pattern of inconsistency.
2. Analyze option B: Looking at the data, it is not clear - cut that plants grow taller with more fertilizer for all trials. For example, in trial 1, the "A lot" amount has a lower average height than "A little" in some cases.
3. Analyze option C: In trial 1, as the amount of fertilizer goes from "None" to "A little" to "A lot", the average height does not show a consistent increase. In fact, the height for "A lot" is lower than for "A little", indicating that more fertilizer may cause less growth.
4. Analyze option D: In trial 2, as the amount of fertilizer increases, the average height generally increases, not decreases.

Answer:

C. The trend in the data for trial 1 shows that more fertilizer causes less growth.