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2.4 Statistical Distributions

2.4 Statistical Distributions

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Question 229

The time, TTT minutes, required for a specific bacterial culture to double in population is modelled by a normal distribution such that T∼N(μ,σ2)T \sim \text{N}(\mu, \sigma^2)T∼N(μ,σ2).

Given that P(T<145)=0.74P(T < 145) = 0.74P(T<145)=0.74, determine:

a.

P(T>145)P(T > 145)P(T>145)

[1]
b.

P(μ<T<145)P(\mu < T < 145)P(μ<T<145)

[2]
c.

P(T>μ∣T<145)P(T > \mu \mid T < 145)P(T>μ∣T<145)

[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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