OCR S1 2013 June — Question 1

Exam BoardOCR
ModuleS1 (Statistics 1)
Year2013
SessionJune
TopicMeasures of Location and Spread
TypeConstruct stem-and-leaf then find median and quartiles

1 The lengths, in centimetres, of 18 snakes are given below. $$\begin{array} { l l l l l l l l l l l l l l l l l l } 24 & 62 & 20 & 65 & 27 & 67 & 69 & 32 & 40 & 53 & 55 & 47 & 33 & 45 & 55 & 56 & 49 & 58 \end{array}$$
  1. Draw an ordered stem-and-leaf diagram for the data.
  2. Find the mean and median of the lengths of the snakes.
  3. It was found that one of the lengths had been measured incorrectly. After this length was corrected, the median increased by 1 cm . Give two possibilities for the incorrect length and give a corrected value in each case.