Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
Some insects of the same kind from two countries, $X$ and $Y$, had their lengths measured. The stem-and-leaf diagram gives the results. Key: $5\,|\,81\,|\,3$ means that an insect from country $X$ has length $0.815\text{ cm}$, while one from country $Y$ has length $0.813\text{ cm}$.
(a)[2]
Find the median value and interquartile range for the lengths of the insects from country $X$.
(b)[2]
The interquartile range for the lengths of the insects from country $Y$ is $0.028\text{ cm}$. Find the values of $q$ and $r$.
(c)[4]
Represent the data with a pair of box-and-whisker plots on a single diagram drawn on graph paper.
(d)[2]
Compare the lengths of the insects from the two countries.
Worked solution & mark scheme
This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Correctly identified median $0.825\text{ cm}$” …