O-LevelMathematicsProbability4024/11 · Oct/Nov 2018 · Q153 Marks

A five-sided spinner is numbered 1, 2, 3, 4 and 5. Ashraf spun the spinner 200 times. The results are shown in the table. Number spinner lands on | 1 | 2 | 3 | 4 | 5 Frequency | 30 | 25 | 50 | 55 | 40 [Table 15.1]

(a)Calculate the relative frequency that the spinner lands on 3.[1]
(b)Meriam spins the spinner 20 times. How many times would you expect the spinner to land on 3?[1]
(c)Ashraf claims: “My results show that the spinner is fair". Is his claim correct? Give a reason for your answer.[1]

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2018). The mark or mark type is shown in brackets.

15(a) 50/200 oe [1]
15(b) 5 [1]
FT 20 × their (a) provided their (a) < 1.
15(c) No, with a supporting reason [1]
e.g.: [has been spun enough times for results to be reliable.]; results are significantly different from those for a fair spinner.

On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.

Topic: Probability, O-Level Mathematics (syllabus 4024). Structured question, 3 marks.
Source: O-Level Mathematics, Oct/Nov 2018 Paper 1 Variant 1, question 15.

Questions and mark schemes are from past examination papers and remain the copyright of the exam board. How Oracle Prep builds its content