Probability and Data — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A line plot has 5 Xs at 2 inches and 2 Xs at 3 inches. Total measurements?
A) 7
B) 5
C) 10
D) 3
Five Xs plus two Xs equals seven total recorded measurements across the line plot's data points.
2. Which question is neutral, not leading?
A) Don't you love the new lunch menu?
B) Which lunch option do you prefer?
C) Why is pizza day always best?
D) Wouldn't you say pasta is great?
Asking which lunch option do you prefer lets respondents pick without pressure, making it a neutral, fair survey question.
3. A bar graph shows 22 apples, 14 oranges, 9 pears. How many fruits total?
A) 22
B) 36
C) 45
D) 31
Twenty-two plus fourteen plus nine equals forty-five total fruits on the bar graph display.
4. Which is the most representative sample of a town?
A) People at one cafe on Monday
B) Members of one sports team only
C) Only neighbors of the surveyor
D) A random selection across many neighborhoods
A random mix from many neighborhoods captures the town's variety, giving the most representative sample for survey results.
Part B: Fill in the Blank
Write the correct answer on each line.
1. On a line plot, 6 Xs at 7 cm means 6 measurements at 7 cm.
Six Xs above the 7 cm mark means six measurements were recorded at exactly seven centimeters.
2. A question that suggests a particular answer is called leading.
Leading questions point to a specific answer, making results less reliable than neutral, well-worded survey questions.
3. A bar graph has 30 red, 20 yellow, 10 blue. Total is 60 items.
Thirty plus twenty plus ten equals sixty total items represented across all three bars in the graph.
4. If 50 students surveyed and 20 picked soccer, the fraction is 20 out of 50.
Survey fractions use the total respondents in the denominator, so twenty out of fifty fairly reflects the soccer count.
5. A fair, varied sample of the whole group is a representative sample.
Representative samples reflect the variety of the entire group, leading to fair and trustworthy survey conclusions.