Mathematics 9709 · AS & A Level · Representation of data

Representation of data — practice question

Helen records the lengths of $150$ fish from one species in a large pond. Their lengths, measured to the nearest centimetre, are displayed in the table below.
(a)[4]

Construct a cumulative frequency graph to represent the data.

(b)[2]

$40\%$ of these fish have a length of $d$ cm or more. Estimate the value of $d$ from your graph.

(c)[3]

The mean length of the $150$ fish is $15.295\text{ cm}$. Estimate the variance of the fish lengths.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Cumulative frequencies correctly given as $15,63,129,150$.

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