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.

Sign in to check answers. Your attempts build your mastery and error book.

2730 questions · page 93 of 137 · choose a topic above to narrow them down

SA-9709-P6-PO1-0022 marksL2 StandardCalculatorProbabilities
X∼Po(4.5)X\sim\text{Po}(4.5). Find P(X<3)P(X<3), correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-PO2-0023 marksL2 StandardCalculatorScaling λ
Breakdowns of a machine occur at random at an average rate of 0.80.8 per day. Find the probability of at most 33 breakdowns in a 77-day week, correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-PO2-0052 marksL2 StandardCalculatorScaling λ
X∼Po(λ)X\sim\text{Po}(\lambda) and P(X=0)=0.2P(X=0)=0.2. Find λ\lambda, correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-PO3-0072 marksL2 StandardCalculatorPoisson for binomial
1.5%1.5\% of components are defective, independently. Use a Poisson approximation to find the probability that a box of 200200 contains no defective components, correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE-0013 marksL2 StandardCalculatorUnbiased estimates
A sample of 5050 values gives Σ(x−20)=35\Sigma(x-20)=35 and Σ(x−20)2=1250\Sigma(x-20)^2=1250. Find unbiased estimates of the population mean and variance (variance to 3 s.f.).

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE-0023 marksL2 StandardCalculatorNormal sample means
X∼N(100,152)X\sim N(100,15^2). A random sample of 2525 is taken. Find P(Xˉ>104)P(\bar X>104), correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE-0044 marksL2 StandardCalculatorCI for a mean
A random sample of 4040 has mean 72.472.4. The population standard deviation is 66. Find a 95%95\% confidence interval for the population mean, with limits to 2 decimal places.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE-0054 marksL2 StandardCalculatorCI for a proportion
In a random sample of 200200 people, 4848 are left-handed. Find a 90%90\% confidence interval for the proportion of left-handed people, with limits to 3 decimal places.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE-0112 marksL2 StandardCalculatorCLT
XX has standard deviation 1212. Find the standard deviation of the mean of a random sample of 3636 values.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE1-0053 marksL2 StandardCalculatorUnbiased estimates
A random sample of 55 values is 3, 5, 6, 8, 83,\ 5,\ 6,\ 8,\ 8. Find unbiased estimates of the population mean and variance.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE2-0043 marksL2 StandardCalculatorNormal sample means
X∼N(200,252)X\sim N(200,25^2). A random sample of 1616 is taken. Find P(195<Xˉ<205)P(195<\bar X<205), correct to 3 significant figures.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE3-0023 marksL2 StandardCalculatorCI for a mean
A random sample of 3636 from a population with standard deviation 1515 has mean 120120. Find a 90%90\% confidence interval for the population mean, with limits to 2 decimal places.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-9709-P6-SE3-0034 marksL2 StandardCalculatorCI for a proportion
In a random sample of 150150 people, 6060 prefer brand A. Find an approximate 95%95\% confidence interval for the proportion of people who prefer brand A, with limits to 3 decimal places.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-AR-0032 marksL2 StandardCalculatorRQ
Calculate the RQ for tripalmitin: 2C51H98O6+145O2→102CO2+98H2O\mathrm{2C_{51}H_{98}O_6+145O_2\rightarrow102CO_2+98H_2O}.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-AR-0041 markL2 StandardCalculatorRQ
An RQ of 1.0 indicates the substrate is
Choose one option

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-AR-0051 markL2 StandardCalculatorGlycolysis
In mammals, anaerobic respiration converts pyruvate to
Choose one option

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-BD-0012 marksL2 StandardCalculatorMeasuring
Counts of four species: 10, 20, 30, 40 (N = 100). Calculate Simpson's index D.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-BD-0022 marksL2 StandardCalculatorMeasuring
50 snails are marked and released. Later, 40 are caught, of which 10 are marked. Estimate the population.

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-BD-0041 markL2 StandardCalculatorClassification
The correct order from largest to smallest group is
Choose one option

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme
SA-AB-BD-0051 markL2 StandardCalculatorMeasuring
A belt transect is best for studying
Choose one option

Sign in or create a free account to check answers, get hints and track your progress.

Salam Academy Original Practice · Proposed mark scheme