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Continuous random variables and the normal distribution — Question 216

Original QCE Vault practice · 5 marks

Q216 · Practice questionTechnology-freeComplex familiar5 marks

QUESTION 216 (5 marks)

The mass

X

of

a

manufactured component is modelled by

N(250,4^{2})

grams.

Original diagram for Mathematical Methods Paper 1 question 16

a)

Express

P(X>258)

in terms of the standard normal variable

Z

.

[1 mark]

b)

Using Phi

(2)=0.9772

, calculate

P(X>258)

.

[2 marks]

c)

Find the

90

th percentile using

z_0.90=1.282

.

[2 marks]

Question linkSyllabus coverage

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