Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
Last Saturday, Sarah noted the colour and style of $160$ cars in a car park. Every car that was neither red nor silver was placed in the ‘other’ group. Her findings are displayed in the table below: Red - Saloon $20$, Hatchback $40$, Estate $12$; Silver - Saloon $14$, Hatchback $26$, Estate $10$; Other - Saloon $6$, Hatchback $24$, Estate $8$.
(i)[1]
Determine the probability that a car selected at random from the car park is a silver estate car.
(ii)[1]
Determine the probability that a car chosen at random from the car park is a hatchback car.
(iii)[2]
Determine the probability that a randomly selected car in the car park is red, given that it is a hatchback car.
(iv)[2]
A car in the car park is selected at random. Decide whether the events ‘the car is a hatchback car’ and ‘the car is red’ are independent, and support your answer with a justification.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme.