STATISTICS AND PROBABILITY 3RD QTR EXAM

VARIABLE

a value that varies

RANDOM VARIABLE DEF

possible values are outcomes of a random process or experiment

ALGEBRA

• small letters

• by assigning or solving

• x + 2

RANDOM VARIABLE

• capital letters

• random processes or event

• x = tossing a coint

DISCRETE

finite number of distinct values

CONTINUOUS

infinite number of values

T = number of tails when tossing two coins

discrete

A = amount of time spent going to school by a randomly selected SHS Teacher​

continuous

Y = temperature in school of  a randomly selected days​

continuous

R = number of dots when rolling a die​

discrete

NORMAL DISTRIBUTIONS

continuous, symmetrical, bell-curved distribution

SYMMETRICAL

characteristic of the normal curve that makes the left half equal to the right half of the curve

ASYMPTOTIC

characteristic of the normal curve that makes the tails of the curve not touch th horizontal axis

EQUAL

the mean, median, and mode of the normal distribution are

1 or 100%

it is the total area under the normal curve

UNIMODAL

characterstic of a normal curve having one mode

68-95-99.7

a rule thats used to approximate the area under the normal curve using the standard deviation

68% ir 0.68

Using the 68-95-99.7 rule, it is the area under the normal curve within one standard deviation.​

What will happen to the normal curve when the population mean changes?​

The curve will either move left or right.​

RIGHT SIDE

increase

LEFT SIDE

decrease

What will happen to the normal curve when the population standard deviation changes?​

The curve will either be flatter and wider or taller and narrower.​

STANDARD DEVIATION INCREASE

shorter + wider

STANDARD DEVIATION DECREASE

taller + narrow

What are the values of the population mean and population standard deviation in a standard normal distribution?​

u = 0, o = 1

PARAMETER

number that describes whole population

STATISTIC

number describing a sample

SIMPLE

equal chance of being selected

SYSTEMATIC

skipping through the list at regular intervals.​

STRATIFIED

divided into groups called strata, then samples are randomly selected from each stratum.

CLUSTER

entire population is divided into small groups, or clusters, and then some of the clusters are randomly selected.

The city of Manila is politically divided into 6 legislative districts

parameter

Fifty students who were randomly selected will participate in a study on the effects of using calculators in learning mathematics

statistic

In a recent research that was conducted in a private school, the subjects of the study were selected by using the Table of Random Numbers

simple

A researcher is doing research work on the students’ reaction to the newly implemented curriculum in Mathematics and interviewed every 10th student entering the gate of the school.

systematic

A researcher interviewed from each town in the province of Albay for his research on population

stratified

A researcher interviewed all top 10 Grade 11 students in each of 15 randomly selected private schools in Metro Manila

cluster