EOC EOC Statistics and Probability 3

Question 1

In a normal distribution, approximately what percentage of data falls within one standard deviation of the mean?

Accepted Answer

68%

Answer

In a normal distribution, approximately 68% of data falls within one standard deviation of the mean, following the empirical rule (68-95-99.7 rule).

Question 2

What is the interquartile range (IQR)?

Accepted Answer

The difference between the third and first quartiles (Q3 − Q1)

Answer

The IQR is Q3 minus Q1 and represents the range of the middle 50% of data, making it resistant to the effects of outliers.

Question 3

Which sampling method involves dividing a population into subgroups and randomly selecting from each subgroup?

Accepted Answer

Stratified random sampling

Answer

Stratified random sampling divides the population into distinct subgroups (strata) and selects a random sample from each stratum to ensure representation.

Question 4

A coin is flipped 3 times. What is the probability of getting exactly 2 heads?

Accepted Answer

3/8

Answer

There are 8 possible outcomes (HHH, HHT, HTH, THH, HTT, THT, TTH, TTT), and 3 contain exactly 2 heads, giving a probability of 3/8.

Question 5

What type of graph is best for displaying the frequency distribution of continuous data?

Accepted Answer

Histogram

Answer

A histogram uses adjacent bars to display the frequency of data within continuous intervals (bins), making it ideal for showing distributions of continuous data.

EOC - End-of-Course Test Practice Test

EOC - End-of-Course Test Practice Test

EOC EOC Statistics and Probability 3