Edexcel A Level Maths – Statistics
Q&A(100%)Correct
Linear Regression - correct answers:y = axⁿ
logy = loga + nlogx
Exponential Regression - correct answers:y = ab^x
logy = loga + xlogb
Normal Approximation - correct answers:µ = np
σ =√(np(1-p))
Mean - correct answers:∑x ÷ n
GF: ∑xf ÷ ∑f
Variance - correct answers:(∑x²/n) - (∑x/n)²
Standard Deviation - correct answers:√variance
Histograms: Height - correct answers:Area = k x frequency
Frequency Density - correct answers:frequency ÷ class width
Population - correct answers:Whole set of items of interest.
,Census - correct answers:Observes/measures every member of a population
Sample - correct answers:Selection of observations taken from a subset of the population which is used
to find out info about the population.
Sampling Frame - correct answers:A list of individuals (named or numbered) from whom the sample is
drawn
Random Sampling - correct answers:Every member of the population has an equal chance of being
selected
Systematic Sampling - correct answers:Every nth person is chosen.
Stratified Sampling - correct answers:Population is divided into mutually exclusive Strat and a random
sample is taken from each.
Quota Sampling - correct answers:Interviewer selects a sample that reflects the characteristics of the
population
Opportunity Sampling - correct answers:Choosing whoever is available
Continuous Variable - correct answers:Can take any value in a given range
Discrete Variable - correct answers:Takes specific values in a given range
Conditions for Binomial - correct answers:Fixed no. of trials
2 possible outcomes
Outcomes are independent
Fixed probability of success
,Probability: Independent if... - correct answers:P(A∩B) = P(A) X P(B)
P(A|B) = P(A)
Probability: Mutually exclusive if... - correct answers:P(A∩B) = 0
P(A∪B) = P(A) + P(B)
Conditional Probability - correct answers:P(A|B) = P(A∩B)/P(B)
Probability Addition Rule - correct answers:P(A∪B) = P(A) + P(B) - P(A∩B)
If there are 3 events, and A and B are mutually exclusive... - correct answers:P(A∪B∪C) = P(A) + P(B) +
P(C) - P(A∩C) - P(B∩C)
What is a DRV - discrete random variable - correct answers:it is a random variable that can only take
certain values
... - correct answers:...
probability mass function - correct answers:a function that gives the probability that a discrete random
variable is exactly equal to some value
what does a probability distribution do - correct answers:describes the probability of any outcome in the
sample space
P(A/B) = - correct answers:(P(A n B))
---------------
P(B)
, If they are independent events P(A) * P(B) = - correct answers:P(A N B)
SUM OF P(X=x) = - correct answers:1
formula for probability X=r where X is the number of desired outcomes
binomial distribution formula - correct answers:nCr P^r * (1-p)^(n-r)
p = probability of success
r = number of times you want success
n= number of trials
standard deviation - correct answers:a computed measure of how much scores vary around the mean
score
general probability addition rule - correct answers:P(A∪B)=P(A)+P(B)−P(A∩B)
P(A∩B)=P(A)+P(B)−P(A∪B)
what is an event - correct answers:a set of possible outcomes - not necessarily equally likely
sample space - correct answers:set of all possible outcomes , all equally likely
A ∪ B - correct answers:means A or B or both
A ∩ B - correct answers:means both A and B
The rules for tree diagrams are - correct answers:Select which branches you need
Multiply along each branch
Q&A(100%)Correct
Linear Regression - correct answers:y = axⁿ
logy = loga + nlogx
Exponential Regression - correct answers:y = ab^x
logy = loga + xlogb
Normal Approximation - correct answers:µ = np
σ =√(np(1-p))
Mean - correct answers:∑x ÷ n
GF: ∑xf ÷ ∑f
Variance - correct answers:(∑x²/n) - (∑x/n)²
Standard Deviation - correct answers:√variance
Histograms: Height - correct answers:Area = k x frequency
Frequency Density - correct answers:frequency ÷ class width
Population - correct answers:Whole set of items of interest.
,Census - correct answers:Observes/measures every member of a population
Sample - correct answers:Selection of observations taken from a subset of the population which is used
to find out info about the population.
Sampling Frame - correct answers:A list of individuals (named or numbered) from whom the sample is
drawn
Random Sampling - correct answers:Every member of the population has an equal chance of being
selected
Systematic Sampling - correct answers:Every nth person is chosen.
Stratified Sampling - correct answers:Population is divided into mutually exclusive Strat and a random
sample is taken from each.
Quota Sampling - correct answers:Interviewer selects a sample that reflects the characteristics of the
population
Opportunity Sampling - correct answers:Choosing whoever is available
Continuous Variable - correct answers:Can take any value in a given range
Discrete Variable - correct answers:Takes specific values in a given range
Conditions for Binomial - correct answers:Fixed no. of trials
2 possible outcomes
Outcomes are independent
Fixed probability of success
,Probability: Independent if... - correct answers:P(A∩B) = P(A) X P(B)
P(A|B) = P(A)
Probability: Mutually exclusive if... - correct answers:P(A∩B) = 0
P(A∪B) = P(A) + P(B)
Conditional Probability - correct answers:P(A|B) = P(A∩B)/P(B)
Probability Addition Rule - correct answers:P(A∪B) = P(A) + P(B) - P(A∩B)
If there are 3 events, and A and B are mutually exclusive... - correct answers:P(A∪B∪C) = P(A) + P(B) +
P(C) - P(A∩C) - P(B∩C)
What is a DRV - discrete random variable - correct answers:it is a random variable that can only take
certain values
... - correct answers:...
probability mass function - correct answers:a function that gives the probability that a discrete random
variable is exactly equal to some value
what does a probability distribution do - correct answers:describes the probability of any outcome in the
sample space
P(A/B) = - correct answers:(P(A n B))
---------------
P(B)
, If they are independent events P(A) * P(B) = - correct answers:P(A N B)
SUM OF P(X=x) = - correct answers:1
formula for probability X=r where X is the number of desired outcomes
binomial distribution formula - correct answers:nCr P^r * (1-p)^(n-r)
p = probability of success
r = number of times you want success
n= number of trials
standard deviation - correct answers:a computed measure of how much scores vary around the mean
score
general probability addition rule - correct answers:P(A∪B)=P(A)+P(B)−P(A∩B)
P(A∩B)=P(A)+P(B)−P(A∪B)
what is an event - correct answers:a set of possible outcomes - not necessarily equally likely
sample space - correct answers:set of all possible outcomes , all equally likely
A ∪ B - correct answers:means A or B or both
A ∩ B - correct answers:means both A and B
The rules for tree diagrams are - correct answers:Select which branches you need
Multiply along each branch
