Mathematics 9709 · AS & A Level · Representation of data

Representation of data — practice question

The times, $t$ minutes, needed by $150$ students to finish a particular challenge are set out in the cumulative frequency table below.
(a)[2]

Draw a cumulative frequency graph to represent the data.

(b)[2]

$24\%$ of the students take $k$ minutes or longer to complete the challenge. Use your graph to estimate the value of $k$.

(c)[6]

Calculate estimates of the mean and the standard deviation of the time needed to complete the challenge.

Worked solution & mark scheme

This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: At least $4$ accurately plotted points with correct scales

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