The histogram shows information about the distance students travel to get to school.

Work out an estimate for the proportion of students who travel more than 4.5km.
Explain why your answer to part a is only an estimate.
Practise OCR GCSE Maths Histograms with exam-style questions for Foundation and Higher tier. 28 questions, matched to the OCR GCSE Maths (J560) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.