Salam Academy
Practise

Question bank

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

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2730 questions · page 39 of 137 · choose a topic above to narrow them down

SA-9709-P5-DV-0082 marksL1 FoundationCalculatorGeometric
X∼Geo(0.3)X\sim\text{Geo}(0.3). Find P(X=4)P(X=4).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0012 marksL1 FoundationCalculatorDistributions
The random variable XX has P(X=x)=k(x+1)P(X=x)=k(x+1) for x=0,1,2,3x=0,1,2,3. Find kk.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0021 markL1 FoundationCalculatorDistributions
XX takes the values 11, 22 and 33 with probabilities 0.20.2, 0.50.5 and pp. Find pp.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0051 markL1 FoundationCalculatorDistributions
XX takes the values 0,1,2,30,1,2,3 with probabilities 0.1, 0.3, 0.4, 0.20.1,\ 0.3,\ 0.4,\ 0.2. Find P(X≥2)P(X\ge2).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0012 marksL1 FoundationCalculatorE(X) and Var(X)
XX takes the values 1,2,31,2,3 with probabilities 0.5, 0.3, 0.20.5,\ 0.3,\ 0.2. Find E(X)E(X).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0052 marksL1 FoundationCalculatorE(X) and Var(X)
A random variable has E(X)=3E(X)=3 and E(X2)=13E(X^2)=13. Find its standard deviation.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0072 marksL1 FoundationCalculatorExpected value in context
Two fair coins are tossed and XX is the number of heads. Find E(X)E(X) and Var(X)\text{Var}(X).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV3-0012 marksL1 FoundationCalculatorBinomial
X∼B(5,0.5)X\sim B(5,0.5). Find P(X=2)P(X=2) as a fraction.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV3-0021 markL1 FoundationCalculatorBinomial
X∼B(12,0.25)X\sim B(12,0.25). Find P(X=0)P(X=0), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV4-0011 markL1 FoundationCalculatorGeometric
X∼Geo(0.2)X\sim\text{Geo}(0.2). Find P(X=3)P(X=3).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV-G014 marksL1 FoundationCalculatorE(X) and Var(X)
XX takes the values 1,2,3,41,2,3,4 with probabilities 0.1,0.3,0.4,0.20.1,0.3,0.4,0.2 respectively. Find E(X)E(X) and Var(X)\text{Var}(X).

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-0012 marksL1 FoundationCalculatorStandardising
X∼N(50,16)X\sim N(50,16). Find P(X>45)P(X>45), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-0131 markL1 FoundationCalculatorStandardising
Z∼N(0,1)Z\sim N(0,1). Find P(Z<−0.5)P(Z<-0.5), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND1-0012 marksL1 FoundationCalculatorStandardising
X∼N(20,25)X\sim N(20,25). Find P(X<27)P(X<27), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND1-0022 marksL1 FoundationCalculatorStandardising
X∼N(60,9)X\sim N(60,9). Find P(X>55)P(X>55), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND2-0011 markL1 FoundationCalculatorInverse normal
Z∼N(0,1)Z\sim N(0,1). Find zz such that P(Z<z)=0.95P(Z<z)=0.95, correct to 3 decimal places.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND3-0012 marksL1 FoundationCalculatorApproximation
X∼B(50,0.4)X\sim B(50,0.4) is to be approximated by Y∼N(μ,σ2)Y\sim N(\mu,\sigma^2). Find μ\mu and σ2\sigma^2.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-G012 marksL1 FoundationCalculatorStandardising
X∼N(50,16)X\sim N(50,16). Find P(X<56)P(X<56), correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-PC-0012 marksL1 FoundationCalculatorRepeats
Find the number of different arrangements of the letters of the word BANANA.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-PC-0061 markL1 FoundationCalculatorSelections
A committee of 44 is to be chosen from 77 men and 55 women. How many different committees are possible?

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Salam Academy Original Practice · Proposed mark scheme