Statistical modellingEdexcel International A Level Maths: Mind map

Exam questions on Statistical modelling

1. A game designer models the result $X$ of a single spin of a spinner that has five sectors, numbered 1 to 5.
   In 200 spins a 3 occurs 41 times. Comment on whether this result supports the model.2 marks
2. A bus company states that its 08:15 bus is late with probability 0.15 on any day. A commuter uses this statement as a model for the number of late buses over 20 weekdays.
   Find the number of late buses that the model predicts over the 20 days. In fact the bus was late on 9 of the 20 days. Comment on the suitability of the model.2 marks
3. A teacher models the score $X$ on one roll of a die by $P(X=x)=\frac16$ for $x=1,2,3,4,5,6$. A student rolls the die 60 times. The scores 1, 2, 3, 4, 5 and 6 occur 7, 12, 9, 11, 8 and 13 times respectively.
   (i) State the expected frequency of each score under the model. (ii) Find the relative frequency of the score 6 from the student's data.3 marks