| Exam Board | AQA |
|---|---|
| Module | AS Paper 2 (AS Paper 2) |
| Year | 2020 |
| Session | June |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Measures of Location and Spread |
| Type | Calculate statistics from large data set |
| Difficulty | Moderate -0.8 Part (a) is a straightforward calculator exercise requiring only the computation of standard deviation from given data (1 mark). Part (b) tests understanding that you cannot simply average two averages without knowing sample sizes—a conceptual point but relatively basic for AS level statistics. The question requires minimal problem-solving and is shorter than typical multi-part questions. |
| Spec | 2.02g Calculate mean and standard deviation |
| Year of registration | 2002 | 2016 |
| Average CO₂ emission | 171.2 | 120.4 |
| Answer | Marks | Guidance |
|---|---|---|
| 15(a) | States (AWRT) 22.9 | |
| Condone (AWRT) 24.1 | 1.1b | B1 |
| Subtotal | 1 |
| Answer | Marks |
|---|---|
| 15(b) | Explains or shows how 145.8 is |
| Answer | Marks | Guidance |
|---|---|---|
| the two years. | 2.4 | E1 |
| Answer | Marks | Guidance |
|---|---|---|
| 2016 is larger than 2002 | 2.4 | E1 |
| Subtotal | 2 | |
| Question Total | 3 | |
| Q | Marking Instructions | AO |
Question 15:
--- 15(a) ---
15(a) | States (AWRT) 22.9
Condone (AWRT) 24.1 | 1.1b | B1 | 22.9
Subtotal | 1
--- 15(b) ---
15(b) | Explains or shows how 145.8 is
generated from the two separate
means
or
Explains that we do not know that
the sample sizes are the same for
the two years. | 2.4 | E1 | (171.2 + 120.4) ÷ 2 = 145.8
However, the sample size for 2016 is
larger so the claim is incorrect
Explains that the sample size for
2016 is larger than 2002 | 2.4 | E1
Subtotal | 2
Question Total | 3
Q | Marking Instructions | AO | Marks | Typical SolutionA random sample of ten CO₂ emissions was selected from the Large Data Set.
The emissions in grams per kilogram were:
13 \quad 45 \quad 45 \quad 0 \quad 49 \quad 77 \quad 49 \quad 49 \quad 49 \quad 78
\begin{enumerate}[label=(\alph*)]
\item Find the standard deviation of the sample.
[1 mark]
\item An environmentalist calculated the average CO₂ emissions for cars in the Large Data Set registered in 2002 and in 2016.
The averages are listed below.
\begin{tabular}{|c|c|c|}
\hline
Year of registration & 2002 & 2016 \\
\hline
Average CO₂ emission & 171.2 & 120.4 \\
\hline
\end{tabular}
The environmentalist claims that the average CO₂ emissions for 2002 and 2016 combined is 145.8
Determine whether this claim is correct.
Fully justify your answer.
[2 marks]
\end{enumerate}
\hfill \mbox{\textit{AQA AS Paper 2 2020 Q15 [3]}}