Mathorio
Answer key
Frequency Tables
Show your work for each problem.
- 1.What does "frequency" mean in a frequency table?
- a)The average of all values
- b)The largest value
- c)The value itself
- d)How many times a value appears
Answer: How many times a value appears
Frequency means how many times a value appears in the data set. It's a count, not the value itself.
- 2.In a frequency table, the values Red: 5, Blue: 8, Green: 3 are listed. What is the total frequency?
- a)8
- b)24
- c)3
- d)16
Answer: 16
Total frequency = . This means there are 16 data points in total.
- 3.A frequency table shows: A: 4, B: 7, C: 9. What is the total number of data points?
Answer: 20
Total data points = . The sum of frequencies equals the total number of data collected.
- 4.What do four tally marks crossed by a fifth line represent? (||||)
Answer: 5
|||| equals 5. Four vertical marks plus one diagonal line crossing them makes counting by fives easy.
- 5.Which category has the highest frequency? | Animal | Frequency | |--------|----------| | Dog | 12 | | Cat | 8 | | Bird | 15 | | Fish | 5 |
- a)Cat
- b)Fish
- c)Dog
- d)Bird
Answer: Bird
Bird has the highest frequency with 15. This means Bird was chosen most often.
- 6.Students were asked their favorite sport. The results: Soccer appeared 8 times, Basketball 5 times, Tennis 3 times, Swimming 4 times. How many students were surveyed?
Answer: 20
Total students = . Each response counts as one student.
- 7.A grouped frequency table has intervals 0-9, 10-19, 20-29. In which interval does the value 19 belong?
- a)10-19
- b)0-9
- c)None of these
- d)20-29
Answer: 10-19
The value 19 belongs in the interval 10-19 because 19 falls within this range (10 ≤ 19 ≤ 19).
- 8.In a class survey, 12 students chose pizza, 8 chose burgers, and 5 chose salad. What fraction of students chose pizza? Write as a simplified fraction (e.g., 1/2).
Answer: 12/25
Total = . Pizza fraction = . This cannot be simplified further.
- 9.Create a frequency table for this data: A, B, A, C, B, A, A, C, B, A. What is the frequency of each letter?
Answer: A:5, B:3, C:2
- How many times does A appear? 5
- How many times does B appear? 3
- How many times does C appear? 2
- What is the total? (Add all frequencies) 10
- 10.The ages of people at a party are: 12, 15, 18, 12, 20, 15, 12, 18, 15, 12. Find the mode (most frequent value).
Answer: 12
- How many times does 12 appear? 4
- How many times does 15 appear? 3
- How many times does 18 appear? 2
- Which age appears most often? 12
- 11.A student made a frequency table but the frequencies sum to 28, while they collected 30 data points. What mistake did they likely make?
- a)Used wrong intervals
- b)Counted some values twice
- c)Made an addition error
- d)Missed counting 2 data points
Answer: Missed counting 2 data points
Since , they missed 2 data points. The frequencies should always equal the total number of data collected.
- 12.Group this data into intervals of 10 (10-19, 20-29, 30-39): 15, 22, 35, 18, 28, 31, 24, 19, 33, 26. Find the frequency for each interval.
Answer: 10-19:3, 20-29:4, 30-39:3
- How many values fall in 10-19? (15, 18, 19) 3
- How many values fall in 20-29? (22, 28, 24, 26) 4
- How many values fall in 30-39? (35, 31, 33) 3
- Verify: What is ? 10
- 13.A store sold shoes in these sizes: 7, 8, 9, 8, 7, 10, 8, 9, 8, 7, 9, 8, 10, 8, 7. What is the relative frequency of size 8? (Write as a decimal, e.g., 0.25)
Answer: 0.4
Size 8 appears 6 times out of 15 total. Relative frequency = or 40%.
- 14.A survey asked 50 people their favorite season. Spring: 12, Summer: 18, Fall: 15, Winter: ?. Find the frequency for Winter and the percentage who prefer Summer.
Answer: Winter: 5, Summer: 36%
- What is ? 45
- Winter frequency = = ? 5
- Summer percentage = = ? 36
- 15.Test scores: 72, 85, 91, 78, 85, 92, 88, 85, 79, 95, 85, 82. Create a grouped frequency table using intervals 70-79, 80-89, 90-99. Which interval has the highest frequency?
Answer: 80-89
- How many scores are in 70-79? (72, 78, 79) 3
- How many scores are in 80-89? (85, 85, 88, 85, 85, 82) 6
- How many scores are in 90-99? (91, 92, 95) 3
- Which interval has the highest frequency? 80-89
- 16.Two classes took a test. Class A: mean score 75, 25 students. Class B: mean score 80, 15 students. If you combine the data, what is the total number of students?
Answer: 40
Total students = Class A + Class B = students. The mean scores are not needed for this calculation.