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The Normal Distribution

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Question 264

In a controlled biochemical reaction, the concentration of enzyme E1, denoted by EEE mg/L, is measured. It is known that EEE follows a normal distribution with a mean of 45.0 and a standard deviation of 3.5.

a.

(i) Find P(E<40.0)P(E < 40.0)P(E<40.0).

(ii) Find P(E>52.5)P(E > 52.5)P(E>52.5).

(iii) A quality control team defines 'optimal concentration' as being between 42.0 mg/L and 48.5 mg/L. Determine the proportion of enzyme samples that meet this criteria.

[6]
b.

The system also monitors the gas pressure, SSS kPa, in the reaction vessel. The pressure SSS is normally distributed with mean μ\muμ and standard deviation σ\sigmaσ.

Environmental data shows that 20% of the pressure readings are less than 15.0 kPa, and 12% of the pressure readings are greater than 22.0 kPa.

Calculate the value of μ\muμ and the value of σ\sigmaσ for the gas pressure.

[6]

The Normal Distribution Questions

  1. A Level
  2. /Maths
  3. /The Normal Distribution

Practise Edexcel A Level Maths The Normal Distribution with exam-style questions for A Level Maths. 439 questions, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.

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