Conditions
What does each letter in “L.I.N.E.R” stand for?
Linear
Independent
Normal
Equal SD
Random
A standard deck of cards contains 52 cards, including 13 hearts. If you draw one card at random, what is the probability that it is a heart?
0.25
“What does ‘%’ represent?”
Percent
Define what a sample is
A small group that represents the entire population.
How do you find the value of X^2 in the calculator?
(Observed - Expected)^2/Expected
How do you know if the sample is random or not?
If the word "random" is stated in the question
There are 3 red marbles, 7 blue marbles, 15 yellow marbles, 4 green marbles, and 5 brown marbles. What is the probability that the marble picked up is green?
8.5
“Only 30% out of the 50 students in the class have turned in their assignments. How many students turned in their assignments?”
15 students
Define what an outlier is
What inputs do you plug in to edit the list?
Stat -> Edit -> L1, L2
How do you identify the 10% condition?
n < 0.10N
n = sample proportion
N = population proportion
A two-digit number is chosen at random. What is the probability that the chosen number is a multiple of 7?
0.13
“A discount of 20% is applied to an item that originally cost $250. What is the discount amount?”
$50
Define what a percentile is
A percentage of observations fall under the given percentile.
What is the function of 2nd - Vars - 3(invNorm)?
Inverse Normal Distribution: Area, Mean, Standard Deviation
What does Equal SD mean?
Standard deviations are the same. Equal amounts of data above and below the regression line.
In a class, 40% of the students like math, 25% like physics, and the other 15% like both. If a student likes math, what is the probability that they also like physics?
0.1875
“In a class of 240 students, 117 are female. What percentage of the class is female?”
48.75%
Define what a correlation is
how two different variables are related to one another
The following numbers represent the number of hours 10 students spent studying for an exam: 3, 5, 7, 8, 8, 9, 11, 12, 15, 18. Find the sample standard deviation and the Interquartile Range (IQR).
Q1: 7
Q3: 12
IQR = 12 - 7 = 5
Sample Standard Deviation: 4.53
What is the rule for each condition of sampling distribution?
Random sample
10%: n < 0.10N
Normal/large count: n _>_ 30
Three cards are drawn from a deck without replacement. What is the probability that they’re all three aces?
4/52 x 3/51 x 2/50 = 24/132,600 divided by 24/24 = 1/5525
“A new medication cures 65% of patients, while the old medication cures 55%. Is this percentage increase statistically significant at the 5% alpha level?”
Yes, because the percentages are not too high and not too low
Define what standard deviation is
the distance between the mean and the data.
A basketball player makes 75% of her free throws. If she takes 10 shots, what is the probability that she makes exactly 6?
1 - 0.75 = 0.25
(0.25)^10-6 = (0.25)^4 = 0.004