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2.4 Statistical Distributions

2.4 Statistical Distributions

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Question 168

For each of the situations in parts (a) to (d), a student is choosing a probability distribution to model the quantity described.

a.

The number of heads obtained when a fair coin is tossed 40 times. Name a suitable distribution, giving its parameters.

[1]
b.

The heights of adult women living in a large town. Name a suitable type of distribution.

[1]
c.

The number of cars passing a particular point on a quiet country lane in a randomly chosen one-minute interval. Explain why neither a binomial nor a normal distribution is a suitable model.

[2]
d.

A student models the mass, in milligrams, of a grain of sand by N(0.6,0.42)N(0.6, 0.4^{2})N(0.6,0.42). Explain, with a supporting calculation, why this model is unsuitable.

[2]
Markscheme

2.4 Statistical Distributions Questions

  1. A Level
  2. /Maths
  3. /2.4 Statistical Distributions

390 exam-style questions on OCR A Level Maths 2.4 Statistical Distributions, covering 2.4.1 Discrete probability distributions, 2.4.2 Binomial distribution as a model, 2.4.3 Calculating binomial probabilities, 2.4.4 Mean and variance of the binomial (A-level only), 2.4.5 Normal distribution as a model (A-level only), 2.4.6 Probabilities using the normal distribution (A-level only), 2.4.7 Links to histograms, mean and standard deviation (A-level only), and 2.4.8 Selecting an appropriate distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

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