Standard +0.3 This is a straightforward one-sample t-test with clearly stated hypotheses, significance level, and normality assumption. Students must calculate sample mean and standard deviation, then perform a standard hypothesis test procedure. While it requires careful execution of multiple steps (calculating statistics, finding critical value, making conclusion), it follows a well-practiced template with no conceptual surprises, making it slightly easier than average for S4 level.
A random sample of 10 mustard plants had the following heights, in mm, after 4 days growth.
5.0, 4.5, 4.8, 5.2, 4.3, 5.1, 5.2, 4.9, 5.1, 5.0
Those grown previously had a mean height of 5.1 mm after 4 days. Using a 2.5\% significance level, test whether or not the mean height of these plants is less than that of those grown previously.
(You may assume that the height of mustard plants after 4 days follows a normal distribution.) [9]
A random sample of 10 mustard plants had the following heights, in mm, after 4 days growth.
5.0, 4.5, 4.8, 5.2, 4.3, 5.1, 5.2, 4.9, 5.1, 5.0
Those grown previously had a mean height of 5.1 mm after 4 days. Using a 2.5\% significance level, test whether or not the mean height of these plants is less than that of those grown previously.
(You may assume that the height of mustard plants after 4 days follows a normal distribution.) [9]
\hfill \mbox{\textit{Edexcel S4 Q2 [9]}}