PractiseQuestion bank
Original exam-style questions, mapped to your syllabus. Answers are checked for mathematical equivalence and every attempt updates your mastery.
Sign in to check answers. Your attempts build your mastery and error book.
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). Find P(X=4). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0012 marksL1 FoundationCalculatorDistributions
The random variable X has P(X=x)=k(x+1) for x=0,1,2,3. Find k. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0021 markL1 FoundationCalculatorDistributions
X takes the values 1, 2 and 3 with probabilities 0.2, 0.5 and p. Find p. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV1-0051 markL1 FoundationCalculatorDistributions
X takes the values 0,1,2,3 with probabilities 0.1, 0.3, 0.4, 0.2. Find P(X≥2). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0012 marksL1 FoundationCalculatorE(X) and Var(X)
X takes the values 1,2,3 with probabilities 0.5, 0.3, 0.2. Find E(X). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0052 marksL1 FoundationCalculatorE(X) and Var(X)
A random variable has E(X)=3 and E(X2)=13. Find its standard deviation. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV2-0072 marksL1 FoundationCalculatorExpected value in context
Two fair coins are tossed and X is the number of heads. Find E(X) and Var(X). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV3-0012 marksL1 FoundationCalculatorBinomial
X∼B(5,0.5). Find P(X=2) as a fraction. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV3-0021 markL1 FoundationCalculatorBinomial
X∼B(12,0.25). Find P(X=0), correct to 3 significant figures. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV4-0011 markL1 FoundationCalculatorGeometric
X∼Geo(0.2). Find P(X=3). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DV-G014 marksL1 FoundationCalculatorE(X) and Var(X)
X takes the values 1,2,3,4 with probabilities 0.1,0.3,0.4,0.2 respectively. Find E(X) and Var(X). Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-0012 marksL1 FoundationCalculatorStandardising
X∼N(50,16). Find P(X>45), correct to 3 significant figures. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-0131 markL1 FoundationCalculatorStandardising
Z∼N(0,1). Find P(Z<−0.5), correct to 3 significant figures. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND1-0012 marksL1 FoundationCalculatorStandardising
X∼N(20,25). Find P(X<27), correct to 3 significant figures. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND1-0022 marksL1 FoundationCalculatorStandardising
X∼N(60,9). Find P(X>55), correct to 3 significant figures. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND2-0011 markL1 FoundationCalculatorInverse normal
Z∼N(0,1). Find z such that P(Z<z)=0.95, correct to 3 decimal places. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND3-0012 marksL1 FoundationCalculatorApproximation
X∼B(50,0.4) is to be approximated by Y∼N(μ,σ2). Find μ and σ2. Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-ND-G012 marksL1 FoundationCalculatorStandardising
X∼N(50,16). Find P(X<56), correct to 3 significant figures. 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.
Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-PC-0061 markL1 FoundationCalculatorSelections
A committee of 4 is to be chosen from 7 men and 5 women. How many different committees are possible? Salam Academy Original Practice · Proposed mark scheme