Ch 6

Question 1

Random Variable

Answer 1

Var whose value is unknown
Example: assigning a value to an expected outcome

Question 2

Discrete

Answer 2

Finite amnt of values
- shoe size
- number of apples
- rating

Question 3

Continuous

Answer 3

infinite values, usually within a range
- measurements (height, volume, etc)
- decimals?? In general???? Given the context obvi lol

Question 4

Show that probability distribution is legit

Answer 4

• 0 <= P(x) <= 1
• Sum of P(x) = 1

Question 5

Describing Histograms
(think ch1.. or 2.. whichever one had describing in general)

Answer 5

SOCS
Shape, Outlier, Center, Spread

Question 6

Normal probability

Answer 6

P (wtv equation with x)

Question 7

Probability – Mean, E(x) Formula

Answer 7

Sum of [ x • P(x) ]

Question 8

Interpret SD

Answer 8

Sum of (probability(x - mean))^2
If you randomly [do smth] many many times, the [unit] will typically vary by [SD] on average from the mean of [mean]

Question 9

Interpret Mean

Answer 9

Sum of (probability × value)
If you randomly [do smth] many many times, the expected [amnt or wtv] would be [mean] on average.

Question 10

How to add mean

Answer 10

Just add them idk

Question 11

How to add SD’s

Answer 11

1. Get variance of each (square SD)
2. Add those together
3. Sqrt root of the sum = final answer

Question 12

What does +/- affect

Answer 12

Mean (centers)

Question 13

What does ×/÷ affect

Answer 13

Mean and SD (centers, spread)

Question 14

Probability Dist

Answer 14

Make a table with x (value) and y (probability). Label accordingly

Question 15

Probability – SD Formula

Answer 15

P × ( x - mean )^2

Question 16

10% condition

Answer 16

n less/equal to (0.10)N

Question 17

AT MOST what calc formula?

Answer 17

Binomial CDF

Question 18

Large count

Answer 18

expect value (np) greater/equal to 10
expect failure (nq) greater/equal to 10