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Continuous random variables and the normal distribution — Question 235

Original QCE Vault practice · 5 marks

Q235 · Practice questionTechnology-activeComplex unfamiliar5 marks

QUESTION 235 (5 marks)

A lifetime

X

(hours) has density

f(x)=c e^{-0.5x}

for

x\ge 0

.

Original diagram for Mathematical Methods Paper 2 question 16

a)

Find

c

.

[2 marks]

b)

Find

P(X>3)

.

[2 marks]

c)

Find the median lifetime.

[1 mark]

Question linkSyllabus coverage

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