Data presentation and diagramsAQA A-Level Maths: Mind map

Exam questions on Data presentation and diagrams

1. A histogram shows the times, in minutes, taken to serve 80 customers. The classes are 0 to 2, 2 to 5, 5 to 10 and 10 to 20 minutes, with frequency densities 10, 8, 4 and 1.6 respectively.
   Estimate the number of customers who took longer than 8 minutes to be served.2 marks
2. A histogram shows the distances, in km, that commuters travel to work. For the class 10 to 15 km the frequency density is 6, for 15 to 25 km it is 3.5, and for 25 to 45 km it is 0.6.
   A student says: 'The bar for 10 to 15 km is the tallest of the three, so more commuters travel 10 to 15 km than travel 15 to 25 km.' Is the student correct? Justify your answer.2 marks
3. The times, in seconds, taken by 100 pupils to complete a puzzle are recorded in classes. The frequencies are 10 for 0 to 20, 30 for 20 to 30, 40 for 30 to 40, 15 for 40 to 60 and 5 for 60 to 100 seconds.
   Find the frequency densities for the classes 0 to 20, 40 to 60 and 60 to 100 seconds.3 marks