ERB Data Analysis and Statistics 3

Question 1

A stem-and-leaf plot shows: Stem 4 | Leaves 2 5 7; Stem 5 | Leaves 0 3 8; Stem 6 | Leaves 1 4. What is the median of this data set?

Accepted Answer

53

Answer

50

Answer

55

Answer

58

Question 2

A researcher surveys 30 out of 300 students in a school to determine favorite after-school activities. This is an example of what type of data collection?

Accepted Answer

Sampling

Answer

Census

Answer

Experiment

Answer

Observational study

Question 3

Which measure of central tendency is MOST affected by an extreme outlier in a data set?

Accepted Answer

Mean

Answer

Median

Answer

Mode

Answer

Range

Question 4

A box plot (box-and-whisker plot) shows: minimum = 10, Q1 = 25, median = 40, Q3 = 55, maximum = 70. What is the interquartile range (IQR)?

Accepted Answer

30

Answer

60

Answer

15

Answer

40

Question 5

A school collects data on student height over five years. The data shows consistent growth each year. What type of graph would BEST display this trend over time?

Accepted Answer

Line graph

Answer

Pie chart

Answer

Bar graph

Answer

Stem-and-leaf plot

Question 6

In a data set of 20 values, 15 values fall below 80. What percentile corresponds to a score of 80?

Accepted Answer

75th percentile

Answer

80th percentile

Answer

15th percentile

Answer

85th percentile

Question 7

A survey of 200 students found that 60% prefer digital books over print. If the school has 850 students, how many students would you predict prefer digital books?

Accepted Answer

510

Answer

480

Answer

500