Practise

Question bank

Original exam-style questions, mapped to your syllabus. Answers are checked for mathematical equivalence and every attempt updates your mastery.

TopicSkillDifficulty

12 questions

SA-9709-P6-LC-0012 marksL1 FoundationCalculatoraX + bY

X

and

Y

are independent with

E(X)=10

\text{Var}(X)=4

E(Y)=6

\text{Var}(Y)=9

. Find

E(X-Y)

and

\text{Var}(X-Y)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-0071 markL1 FoundationCalculatoraX + bY

X\sim\text{Po}(2)

. Which of these has a Poisson distribution?

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-0081 markL1 FoundationCalculatoraX + b

\text{Var}(X)=3

. Find

\text{Var}(5-2X)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC1-0012 marksL1 FoundationCalculatoraX + b

E(X)=8

and

\text{Var}(X)=2

. Find

E(4X+1)

and

\text{Var}(4X+1)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC1-0021 markL1 FoundationCalculatoraX + b

The standard deviation of

X

3

. Find the standard deviation of

2X-5

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC1-0051 markL1 FoundationCalculatoraX + bY

The result

\text{Var}(X+Y)=\text{Var}(X)+\text{Var}(Y)

requires that

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-G012 marksL1 FoundationCalculatoraX + b

E(X)=5

and

\text{Var}(X)=4

. Find

E(3X-2)

and

\text{Var}(3X-2)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-Q011 markL1 FoundationCalculatoraX + b

\text{Var}(aX+b)

equals

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-Q021 markL1 FoundationCalculatoraX + bY

For independent

X

and

Y

\text{Var}(X-Y)

equals

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC-0112 marksL2 StandardCalculatoraX + bY

X

and

Y

are independent with

E(X)=4

\text{Var}(X)=1

E(Y)=3

\text{Var}(Y)=2

. Find

E(2X+3Y)

and

\text{Var}(2X+3Y)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC1-0033 marksL2 StandardCalculatoraX + bY

X

and

Y

are independent with

E(X)=12

\text{Var}(X)=5

E(Y)=7

and

\text{Var}(Y)=3

. Find

E(2X-3Y)

and

\text{Var}(2X-3Y)

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P6-LC1-0043 marksL3 ExamCalculatoraX + b

Temperatures

F

in °F have mean

68

and variance

81

. Find the mean and variance of the temperatures in °C, where

C=\dfrac{F-32}{1.8}

Salam Academy Original Practice · Proposed mark scheme