Edexcel S1 2012 January — Question 1 4 marks

Exam BoardEdexcel
ModuleS1 (Statistics 1)
Year2012
SessionJanuary
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicData representation
TypeComplete frequency table from histogram only
DifficultyEasy -1.2 This is a straightforward histogram interpretation question requiring students to use the relationship frequency = class width × frequency density. The calculations are simple arithmetic with no conceptual challenges beyond understanding this basic formula, making it easier than average for A-level.
Spec2.02b Histogram: area represents frequency

  1. The histogram in Figure 1 shows the time, to the nearest minute, that a random sample of 100 motorists were delayed by roadworks on a stretch of motorway.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{bc8ef6c7-a321-4ecf-962d-f469a95fc8c8-02_1312_673_349_639} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure}
  1. Complete the table.
    Delay (minutes)Number of motorists
    4-66
    7-8
    921
    10-1245
    13-159
    16-20
  2. Estimate the number of motorists who were delayed between 8.5 and 13.5 minutes by the roadworks.

AnswerMarks Guidance
(a) \(14, 5\)M1 A1 M1 for \(2×7\) or \(14\) or \(5×1\) or \(5\); A1 for both \(14\) and \(5\)
(2 marks)
(b) \(21 + 45 + 3 = 69\)M1 A1 M1 for \(21+45+(0<\text{frequency}<9)\); A1 for \(69\) only. If \(69\) with no working, award M1A1. Incorrect answer with no working M0A0.
(2 marks)
Total: 4 marks
**(a)** $14, 5$ | M1 A1 | M1 for $2×7$ or $14$ or $5×1$ or $5$; A1 for both $14$ and $5$
| | (2 marks) |

**(b)** $21 + 45 + 3 = 69$ | M1 A1 | M1 for $21+45+(0<\text{frequency}<9)$; A1 for $69$ only. If $69$ with no working, award M1A1. Incorrect answer with no working M0A0.
| | (2 marks) |

**Total: 4 marks**

---
\begin{enumerate}
  \item The histogram in Figure 1 shows the time, to the nearest minute, that a random sample of 100 motorists were delayed by roadworks on a stretch of motorway.
\end{enumerate}

\begin{figure}[h]
\begin{center}
  \includegraphics[alt={},max width=\textwidth]{bc8ef6c7-a321-4ecf-962d-f469a95fc8c8-02_1312_673_349_639}
\captionsetup{labelformat=empty}
\caption{Figure 1}
\end{center}
\end{figure}

(a) Complete the table.

\begin{center}
\begin{tabular}{|l|l|}
\hline
Delay (minutes) & Number of motorists \\
\hline
4-6 & 6 \\
\hline
7-8 &  \\
\hline
9 & 21 \\
\hline
10-12 & 45 \\
\hline
13-15 & 9 \\
\hline
16-20 &  \\
\hline
\end{tabular}
\end{center}

(b) Estimate the number of motorists who were delayed between 8.5 and 13.5 minutes by the roadworks.

\hfill \mbox{\textit{Edexcel S1 2012 Q1 [4]}}