t (min)0≤t<55≤t<1010≤t<2020≤t<50frequency18324030\begin{array}{c|rrrr}t\text{ (min)}&0\leq t<5&5\leq t<10&10\leq t<20&20\leq t<50\\\hline\text{frequency}&18&32&40&30\end{array}t (min)frequency0≤t<5185≤t<103210≤t<204020≤t<5030
Calculate the frequency densities and identify the modal class.
A student says the widest bar must contain the most observations. Explain the error.
105 exam-style questions on WJEC A Level Maths 2.2 Data presentation and interpretation, covering 2.2.1 Data presentation and interpretation, 2.2.2 Data presentation and interpretation, 2.2.3 Data presentation and interpretation, 2.2.4 Data presentation and interpretation, 2.2.5 Data presentation and interpretation, 2.2.6 Data presentation and interpretation, 2.2.7 Data presentation and interpretation, 2.2.8 Data presentation and interpretation, and 2.2 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.