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Data presentation - Stem & Leaf plots.
Test Yourself 1.

1 sided 1.

8. The number of people attending a Vaccination Centre for the Astra jab was recorded at the end of each two hour time period for 3 days. The date are summarised in the following stem & leaf plot:
 1 *, 4 2 0, 3, 5, 5, 8 3 2, 3, 6, 6, 6, 8 4 0, 0, 1, 4, 5, 9 5 0, 1, 1, 3, 5

(i) The range over these 3 days of the number of patients in a 2 hour period was 42. What is the missing number (*) in the data?

(ii) What was the mode number of patients attending across the two hour periods?

(iii) What was the inter-quartile range for the number of patients attending across the two hour periods?

(iv) How many patients attended the Centre within the inter-quartile range?

(v) Write down a five figure summary for this set of observations.

(ii) Mode is 36 patients in
the 2 hour period.
(iii) IQR = 20.5.
(iv) 449 patients attended.
(v) [13, 26.5, 37, 47, 55].

2 sided 11.

15. The ages of people attending a meeting of the local sports club are recorded in a table separately for males and females.
 Males Females 6 1 2 521 2 1355 98721 3 122 8521 4 56

What is the median age of the females who attended?