AQA AS Paper 2 2024 June — Question 16 5 marks

Exam BoardAQA
ModuleAS Paper 2 (AS Paper 2)
Year2024
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMeasures of Location and Spread
TypeCalculate statistics from large data set
DifficultyEasy -1.8 This is a straightforward AS-level statistics question requiring only direct application of standard formulas for mean (Σx/n) and standard deviation (√(Σx²/n - x̄²)). Part (b) asks for basic interpretation about sampling and recall of dataset information. All calculations are routine with no problem-solving or conceptual challenge beyond formula recall.
Spec2.02g Calculate mean and standard deviation

An investigation into the hydrocarbon emissions, \(X\) g/km, from cars in the Large Data Set was carried out. The results are summarised below. $$\sum x = 128.657 \qquad \sum x^2 = 8.701 \, 707 \qquad n = 2405$$ where \(n\) is the total number of cars which had a measured hydrocarbon emission in the Large Data Set.
    1. Find the mean of \(X\) [1 mark]
    2. Find the standard deviation of \(X\) [2 marks]
    1. The Large Data Set is a sample taken from the entire UK Department for Transport Stock Vehicle Database. It is claimed that the values in part (a)(i) and part (a)(ii) obtained from the Large Data Set should be reliable estimates for the mean and standard deviation of the hydrocarbon emissions for the entire UK Department for Transport Stock Vehicle Database. State, with a reason, whether this claim is likely to be correct. [1 mark]
    2. State one type of emission where more than 80% of the data is known for cars in the entire UK Department for Transport Stock Vehicle Database. [1 mark]

Question 16:

AnswerMarks Guidance
16(a)(i)Obtains correct mean
AWFW [0.053, 0.054]1.1b B1
Mean = = 0.053496
2 4 0 5
AnswerMarks Guidance
Subtotal1
QMarking instructions AO

AnswerMarks
16(a)(ii)Obtains a value of the standard
deviation in the range
AnswerMarks Guidance
[0.0265, 0.0285]1.1b B1
8.701707 128.657
Sd = −  
2405  2405 
= 0 . 0 0 0 7 5 6 3 9
= 0.0275
Obtains value of the standard
deviation
AnswerMarks Guidance
AWRT 0.02751.1b B1
Subtotal2
QMarking instructions AO

AnswerMarks
16(b)(i)States that the claim is/may be
incorrect.
With a valid reason
Eg
Not every make of car is
included in the LDS
LDS does not reflect number of
electric, gas/petrol in UK
database
Not every region is included in
the LDS
LDS only comes from 2 years
LDS is a small sample
compared to the entire UK
AnswerMarks Guidance
database2.2b E1
from every region of the UK, so the
claim may be incorrect.
AnswerMarks Guidance
Subtotal1
QMarking instructions AO

AnswerMarks Guidance
16(b)(ii)States CO , CO or NOX
21.2 B1
2
AnswerMarks Guidance
Subtotal1
Question 16 Total5
QMarking instructions AO
Question 16:
--- 16(a)(i) ---
16(a)(i) | Obtains correct mean
AWFW [0.053, 0.054] | 1.1b | B1 | 1 2 8 .6 5 7
Mean = = 0.053496
2 4 0 5
Subtotal | 1
Q | Marking instructions | AO | Marks | Typical solution
--- 16(a)(ii) ---
16(a)(ii) | Obtains a value of the standard
deviation in the range
[0.0265, 0.0285] | 1.1b | B1 | 2
8.701707 128.657
Sd = −  
2405  2405 
= 0 . 0 0 0 7 5 6 3 9
= 0.0275
Obtains value of the standard
deviation
AWRT 0.0275 | 1.1b | B1
Subtotal | 2
Q | Marking instructions | AO | Marks | Typical solution
--- 16(b)(i) ---
16(b)(i) | States that the claim is/may be
incorrect.
With a valid reason
Eg
Not every make of car is
included in the LDS
LDS does not reflect number of
electric, gas/petrol in UK
database
Not every region is included in
the LDS
LDS only comes from 2 years
LDS is a small sample
compared to the entire UK
database | 2.2b | E1 | The LDS does not include cars
from every region of the UK, so the
claim may be incorrect.
Subtotal | 1
Q | Marking instructions | AO | Marks | Typical solution
--- 16(b)(ii) ---
16(b)(ii) | States CO , CO or NOX
2 | 1.2 | B1 | CO
2
Subtotal | 1
Question 16 Total | 5
Q | Marking instructions | AO | Marks | Typical solution
An investigation into the hydrocarbon emissions, $X$ g/km, from cars in the Large Data Set was carried out.

The results are summarised below.
$$\sum x = 128.657 \qquad \sum x^2 = 8.701 \, 707 \qquad n = 2405$$

where $n$ is the total number of cars which had a measured hydrocarbon emission in the Large Data Set.

\begin{enumerate}[label=(\alph*)]
\item \begin{enumerate}[label=(\roman*)]
\item Find the mean of $X$
[1 mark]

\item Find the standard deviation of $X$
[2 marks]
\end{enumerate}

\item \begin{enumerate}[label=(\roman*)]
\item The Large Data Set is a sample taken from the entire UK Department for Transport Stock Vehicle Database.

It is claimed that the values in part (a)(i) and part (a)(ii) obtained from the Large Data Set should be reliable estimates for the mean and standard deviation of the hydrocarbon emissions for the entire UK Department for Transport Stock Vehicle Database.

State, with a reason, whether this claim is likely to be correct.
[1 mark]

\item State one type of emission where more than 80% of the data is known for cars in the entire UK Department for Transport Stock Vehicle Database.
[1 mark]
\end{enumerate}
\end{enumerate}

\hfill \mbox{\textit{AQA AS Paper 2 2024 Q16 [5]}}