Representing dataIB MYP Maths Extended: Mind map

Exam questions on Representing data

1. A class of 30 students chose their favourite sport: football 12, swimming 8, tennis 6 and other sports 4.
   Maria says that a line graph is the best way to show this data. Explain why she is wrong and suggest a better representation.2 marks
2. Eleven students scored these marks in a test: 34, 41, 45, 38, 52, 47, 41, 36, 58, 45 and 41. The marks are shown in an ordered stem-and-leaf diagram with stems 3, 4 and 5. The key is 4 | 1 means 41.
   Find the range of the marks and state one advantage of a stem-and-leaf diagram over a grouped frequency table.2 marks
3. A café owner records the highest temperature (in °C) and the number of cold drinks sold on six days. The pairs (temperature, drinks sold) are (14, 20), (18, 35), (21, 48), (25, 60), (28, 78) and (30, 85).
   Describe the relationship between temperature and drinks sold, and explain why the owner should not use this data to predict sales on a day when the temperature is $40^\circ$C.3 marks