SPS SPS FM Statistics 2021 June — Question 5 7 marks

Exam BoardSPS
ModuleSPS FM Statistics (SPS FM Statistics)
Year2021
SessionJune
Marks7
TopicMeasures of Location and Spread
TypeAdding data values
DifficultyModerate -0.3 This is a straightforward application of updating mean and standard deviation formulas when adding a data point. Part (i) requires careful but routine calculation with the formulas for combining datasets. Part (ii) tests understanding of outliers using a standard criterion (likely 2 standard deviations). The calculations are mechanical with no conceptual difficulty or problem-solving insight required, making it slightly easier than average.
Spec2.02g Calculate mean and standard deviation2.02h Recognize outliers

Eleven students in a class sit a Mathematics exam and their average score is 67% with a standard deviation of 12%. One student from the class is absent and sits the paper later, achieving a score of 85%.
  1. Find the mean score for the whole class and the standard deviation for the whole class. [5]
  2. Comment, with justification, on whether the score for the paper sat later should be considered as an outlier. [2]

Eleven students in a class sit a Mathematics exam and their average score is 67% with a standard deviation of 12%.

One student from the class is absent and sits the paper later, achieving a score of 85%.

\begin{enumerate}[label=(\roman*)]
\item Find the mean score for the whole class and the standard deviation for the whole class. [5]
\item Comment, with justification, on whether the score for the paper sat later should be considered as an outlier. [2]
\end{enumerate}

\hfill \mbox{\textit{SPS SPS FM Statistics 2021 Q5 [7]}}