NJGPA Statistics, Data Analysis, and Probability 3

Question 1

Which sampling method involves randomly selecting participants from a complete list of the entire population?

Accepted Answer

Simple random sampling

Answer

Simple random sampling gives every member of the population an equal chance of being selected from the complete list.

Question 2

A data set contains the values 2, 5, 5, 6, 7, 8, 50. Which measure of central tendency would be most misleading when summarizing this data?

Accepted Answer

Mean

Answer

The outlier 50 dramatically pulls the mean upward, making it unrepresentative of the rest of the data.

Question 3

A two-way frequency table shows data on gender and preference for a school mascot. There are 80 students total. If 40 are boys and 25 boys prefer the eagle mascot, what fraction of boys prefer the eagle?

Accepted Answer

5/8

Answer

25 out of 40 boys prefer the eagle: 25/40 = 5/8.

Question 4

A histogram displays test scores in intervals of 10. The bar for 70–79 has a frequency of 15, and the bar for 80–89 has a frequency of 20. What is the total number of students who scored between 70 and 89?

Accepted Answer

35

Answer

Add the frequencies for both intervals: 15 + 20 = 35 students total.

Question 5

A student rolls a standard 6-sided die. What is the probability of rolling a number greater than 4?

Accepted Answer

1/3

Answer

Numbers greater than 4 on a die are 5 and 6 — that is 2 out of 6 outcomes, which simplifies to 1/3.

(NJGPA) New Jersey Graduation Proficiency Assessment Practice Test

(NJGPA) New Jersey Graduation Proficiency Assessment Practice Test

NJGPA Statistics, Data Analysis, and Probability 3