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

50%

Answer

95%

Answer

99.7%

Question 2

What is the interquartile range (IQR)?

Accepted Answer

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

Answer

The difference between the max and min values

Answer

The average of the upper and lower halves

Answer

The middle 25% of data

Question 3

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

Accepted Answer

Stratified random sampling

Answer

Simple random sampling

Answer

Convenience sampling

Answer

Systematic sampling

Question 4

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

Accepted Answer

3/8

Answer

1/8

Answer

2/8

Answer

4/8

Question 5

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

Accepted Answer

Histogram

Answer

Bar graph

Answer

Pie chart

Answer

Line graph

Question 6

What does it mean when we say a sample is 'biased'?

Accepted Answer

The sample does not accurately represent the population

Answer

The sample is very large

Answer

The sample was randomly selected

Answer

The sample has no outliers