Edexcel A Level Maths - Statistics Exam
Questions and Answers 2024 Review
100% Pass
Linear Regression - Answer>>y = axⁿ
logy = loga + nlogx
Exponential Regression - Answer>>y = ab^x
logy = loga + xlogb
Normal Approximation - Answer>>µ = np
σ =√(np(1-p))
Mean - Answer>>∑x ÷ n
GF: ∑xf ÷ ∑f
Variance - Answer>>(∑x²/n) - (∑x/n)²
Standard Deviation - Answer>>√variance
Histograms: Height - Answer>>Area = k x frequency
Frequency Density - Answer>>frequency ÷ class width
Population - Answer>>Whole set of items of interest.
Census - Answer>>Observes/measures every member of a
population
,Sample - Answer>>Selection of observations taken from a
subset of the population which is used to find out info about the
population.
Sampling Frame - Answer>>A list of individuals (named or
numbered) from whom the sample is drawn
Random Sampling - Answer>>Every member of the population
has an equal chance of being selected
Systematic Sampling - Answer>>Every nth person is chosen.
Stratified Sampling - Answer>>Population is divided into
mutually exclusive Strat and a random sample is taken from each.
Quota Sampling - Answer>>Interviewer selects a sample that
reflects the characteristics of the population
Opportunity Sampling - Answer>>Choosing whoever is
available
Continuous Variable - Answer>>Can take any value in a given
range
Discrete Variable - Answer>>Takes specific values in a given
range
Conditions for Binomial - Answer>>Fixed no. of trials
2 possible outcomes
Outcomes are independent
Fixed probability of success
Probability: Independent if... - Answer>>P(A∩B) = P(A) X P(B)
,P(A|B) = P(A)
Probability: Mutually exclusive if... - Answer>>P(A∩B) = 0
P(A∪B) = P(A) + P(B)
Conditional Probability - Answer>>P(A|B) = P(A∩B)/P(B)
Probability Addition Rule - Answer>>P(A∪B) = P(A) + P(B) -
P(A∩B)
If there are 3 events, and A and B are mutually exclusive... -
Answer>>P(A∪B∪C) = P(A) + P(B) + P(C) - P(A∩C) - P(B∩C)
What is a DRV - discrete random variable - Answer>>it is a
random variable that can only take certain values
... - Answer>>...
probability mass function - Answer>>a function that gives the
probability that a discrete random variable is exactly equal to
some value
what does a probability distribution do - Answer>>describes the
probability of any outcome in the sample space
P(A/B) = - Answer>>(P(A n B))
---------------
P(B)
If they are independent events P(A) * P(B) = - Answer>>P(A N
B)
SUM OF P(X=x) = - Answer>>1
, formula for probability X=r where X is the number of desired
outcomes
binomial distribution formula - Answer>>nCr P^r * (1-p)^(n-r)
p = probability of success
r = number of times you want success
n= number of trials
standard deviation - Answer>>a computed measure of how
much scores vary around the mean score
general probability addition rule - Answer>>P(A∪B)=P(A)+P(B)
−P(A∩B)
P(A∩B)=P(A)+P(B)−P(A∪B)
what is an event - Answer>>a set of possible outcomes - not
necessarily equally likely
sample space - Answer>>set of all possible outcomes , all
equally likely
A ∪ B - Answer>>means A or B or both
A ∩ B - Answer>>means both A and B
The rules for tree diagrams are - Answer>>Select which
branches you need
Multiply along each branch
Add the results of each branch needed.
Make sure that you include enough working to show which
branches you are using (method).
Be careful to allow for selection with and without replacement.
Questions and Answers 2024 Review
100% Pass
Linear Regression - Answer>>y = axⁿ
logy = loga + nlogx
Exponential Regression - Answer>>y = ab^x
logy = loga + xlogb
Normal Approximation - Answer>>µ = np
σ =√(np(1-p))
Mean - Answer>>∑x ÷ n
GF: ∑xf ÷ ∑f
Variance - Answer>>(∑x²/n) - (∑x/n)²
Standard Deviation - Answer>>√variance
Histograms: Height - Answer>>Area = k x frequency
Frequency Density - Answer>>frequency ÷ class width
Population - Answer>>Whole set of items of interest.
Census - Answer>>Observes/measures every member of a
population
,Sample - Answer>>Selection of observations taken from a
subset of the population which is used to find out info about the
population.
Sampling Frame - Answer>>A list of individuals (named or
numbered) from whom the sample is drawn
Random Sampling - Answer>>Every member of the population
has an equal chance of being selected
Systematic Sampling - Answer>>Every nth person is chosen.
Stratified Sampling - Answer>>Population is divided into
mutually exclusive Strat and a random sample is taken from each.
Quota Sampling - Answer>>Interviewer selects a sample that
reflects the characteristics of the population
Opportunity Sampling - Answer>>Choosing whoever is
available
Continuous Variable - Answer>>Can take any value in a given
range
Discrete Variable - Answer>>Takes specific values in a given
range
Conditions for Binomial - Answer>>Fixed no. of trials
2 possible outcomes
Outcomes are independent
Fixed probability of success
Probability: Independent if... - Answer>>P(A∩B) = P(A) X P(B)
,P(A|B) = P(A)
Probability: Mutually exclusive if... - Answer>>P(A∩B) = 0
P(A∪B) = P(A) + P(B)
Conditional Probability - Answer>>P(A|B) = P(A∩B)/P(B)
Probability Addition Rule - Answer>>P(A∪B) = P(A) + P(B) -
P(A∩B)
If there are 3 events, and A and B are mutually exclusive... -
Answer>>P(A∪B∪C) = P(A) + P(B) + P(C) - P(A∩C) - P(B∩C)
What is a DRV - discrete random variable - Answer>>it is a
random variable that can only take certain values
... - Answer>>...
probability mass function - Answer>>a function that gives the
probability that a discrete random variable is exactly equal to
some value
what does a probability distribution do - Answer>>describes the
probability of any outcome in the sample space
P(A/B) = - Answer>>(P(A n B))
---------------
P(B)
If they are independent events P(A) * P(B) = - Answer>>P(A N
B)
SUM OF P(X=x) = - Answer>>1
, formula for probability X=r where X is the number of desired
outcomes
binomial distribution formula - Answer>>nCr P^r * (1-p)^(n-r)
p = probability of success
r = number of times you want success
n= number of trials
standard deviation - Answer>>a computed measure of how
much scores vary around the mean score
general probability addition rule - Answer>>P(A∪B)=P(A)+P(B)
−P(A∩B)
P(A∩B)=P(A)+P(B)−P(A∪B)
what is an event - Answer>>a set of possible outcomes - not
necessarily equally likely
sample space - Answer>>set of all possible outcomes , all
equally likely
A ∪ B - Answer>>means A or B or both
A ∩ B - Answer>>means both A and B
The rules for tree diagrams are - Answer>>Select which
branches you need
Multiply along each branch
Add the results of each branch needed.
Make sure that you include enough working to show which
branches you are using (method).
Be careful to allow for selection with and without replacement.
