STRAIGHTERLINE INTRODUCTION TO STATISTICS EXAM 2026|2027 UPDATED QUESTIONS WITH DETAILED VERIFIED ANSWERS | ALREADY GRADED A+

STRAIGHTERLINE INTRODUCTION TO STATISTICS EXAM 2026|2027
UPDATED QUESTIONS WITH DETAILED VERIFIED ANSWERS | ALREADY
GRADED A+

Center of a random variable distribution is measured by its - CORRECT ANSWER -mean




Spread of a random variable distribution is measured by its - CORRECT ANSWER -variance or standard
deviation




Rules for the linear transformation of one random variable - CORRECT ANSWER -μ(a+b)X=a+b μX
σ^2a+bX=b^2σ^2X




1. Usual
2. Unusual - CORRECT ANSWER -1. Within two standards deviations of the mean
2. More than two standard deviations above or below the mean




Binomial Experiment - CORRECT ANSWER -1. a fixed number of trials (notation: n trials)
2. each trial must be independent of the others
3. each trial has two possible outcomes, called "success" (the outcome of interest) and "failure"


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, 4. there is a constant probability (p) of success for each trial, the complement of which is the probability
(1 - p) of failure




Binomials
The Number of outcomes with x successes out of n trials (formula) - CORRECT ANSWER -[n!]/[x!*(n-x)!]




Mean of a binomial - CORRECT ANSWER -μX=np




z-score for normal random variable - CORRECT ANSWER -z=(x−μ)/σ




1. Parameter
2. Statistic - CORRECT ANSWER -1. Number that describes the population
2. Number that is computed from the sample




Standard deviation of all sample proportions - CORRECT ANSWER -√{[p(1−p)]/n}.




Standard deviation of all sample means - CORRECT ANSWER -σ/(√n)



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