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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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12 questions

SA-9709-P5-DR-0112 marksL1 FoundationCalculatorCoding
The values of xx have mean 1010 and standard deviation 44. Each value is changed using y=2x+3y=2x+3. Find the mean and standard deviation of yy.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0013 marksL1 FoundationCalculatorCoding
For 2020 values, Σ(x−100)=60\Sigma(x-100)=60 and Σ(x−100)2=500\Sigma(x-100)^2=500. Find the mean and standard deviation of xx.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0032 marksL1 FoundationCalculatorCoding
A data set has mean 3030 and standard deviation 55. Every value is multiplied by 33 and then 1010 is subtracted. Find the new mean and standard deviation.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0042 marksL1 FoundationCalculatorCombining sets
Group A has 1010 values with mean 2020; group B has 1515 values with mean 2525. Find the mean of all 2525 values.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR-Q011 markL1 FoundationCalculatorCoding
Adding 55 to every value in a data set
Choose one option

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR-0024 marksL2 StandardCalculatorCoding
For 1212 values of xx, Σ(x−50)=36\Sigma(x-50)=36 and Σ(x−50)2=420\Sigma(x-50)^2=420. Find the mean and the standard deviation of xx, correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0022 marksL2 StandardCalculatorCoding
The coded values y=x−5010y=\dfrac{x-50}{10} have mean 2.42.4 and standard deviation 0.80.8. Find the mean and standard deviation of xx.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0054 marksL2 StandardCalculatorCombining sets
Set A: n=8n=8, Σx=80\Sigma x=80, Σx2=880\Sigma x^2=880. Set B: n=12n=12, Σx=150\Sigma x=150, Σx2=1950\Sigma x^2=1950. Find the mean and standard deviation (3 s.f.) of the combined 2020 values.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0072 marksL2 StandardCalculatorCoding
For 1010 values, Σ(x−a)=30\Sigma(x-a)=30, and the mean of xx is 2525. Find aa.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR-0104 marksL3 ExamCalculatorCombining sets
Set A: n=10n=10, Σx=50\Sigma x=50, Σx2=290\Sigma x^2=290. Set B: n=15n=15, Σx=90\Sigma x=90, Σx2=600\Sigma x^2=600. Find the mean and standard deviation of the combined set of 2525 values, the standard deviation correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR4-0065 marksL3 ExamCalculatorCombining sets
Group A: 55 values with mean 1010 and standard deviation 22. Group B: 55 values with mean 1414 and standard deviation 22. Find the standard deviation of all 1010 values combined, correct to 3 significant figures.

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Salam Academy Original Practice · Proposed mark scheme
SA-9709-P5-DR-0155 marksL4 ChallengingCalculatorCoding
For 1515 values, Σ(x−20)=−15\Sigma(x-20)=-15 and Σ(x−20)2=105\Sigma(x-20)^2=105. Find the mean and standard deviation of xx (standard deviation to 3 significant figures), and hence find Σx2\Sigma x^2.

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Salam Academy Original Practice · Proposed mark scheme