Line Plots with Fractions — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. A scientist measures lengths of 10 bugs in inches: 14, 12, 14, 34, 12, 14, 12, 34, 12, 14. How many X marks are at 14 on the line plot?
Answer: 4
Counting through the bug-length list, the value 14 appears at positions 1, 3, 6, and 10, which is 4 times total. On a line plot, each repeated measurement becomes one X stacked above that value, so 14 needs 4 X marks.
2. Using the same bug data above, how many X marks are at 12 on the line plot?
Answer: 4
Scanning the same list for 12, it appears at positions 2, 5, 7, and 9 — 4 occurrences. Each occurrence is plotted as a single X above 12, giving 4 X marks at that location.
3. Using the same bug data above, how many X marks are at 34 on the line plot?
Answer: 2
The value 34 shows up at positions 4 and 8 in the bug-length list, so it occurs 2 times. Each of those measurements becomes one X above 34, producing 2 X marks.
4. Using the same bug data, the mode(s) of the data set is/are 14 and 12.
Both 14 and 12 appear 4 times — the highest frequency. When two values tie for the most appearances, both are modes (bimodal data set).
5. A line plot shows rainfall for 12 days: 0→2 Xs, 18→3 Xs, 14→4 Xs, 38→2 Xs, 12→1 X. The most common rainfall amount is 14 inch.
14 inch has the most X marks (4), making it the mode — the most common rainfall amount.
6. Using the rainfall data above, the number of days with more than 18 inch of rain is 7.
More than 18 inch: 14(4) + 38(2) + 12(1) = 4 + 2 + 1 = 7 days.
7. Students long-jumped (meters): 34, 12, 1, 34, 12, 14, 34, 12, 1, 34. The value with the most X marks is 34 meter.
Count: 14→1, 12→3, 34→4, 1→2. The value with the most X marks (4) is 34 meter.
8. Using the long-jump data, the number of students who jumped 12 meter or less is 4.
12 meter or less: 14(1) + 12(3) = 1 + 3 = 4 students.
9. Using the long-jump data, the difference between the count at 34 meter and the count at 14 meter is 3.
Count at 34 = 4. Count at 14 = 1. Difference = 4 − 1 = 3.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Data: 14, 12, 14, 34, 12, 14. How many X marks at 14?
→ 3
38
Data: 18, 38, 38, 58, 38, 38, 18, 58. What is the mode?
→ 38
5
Line plot: 14→5 Xs, 12→3 Xs, 34→2 Xs. Total data points?
→ 10
3
Line plot: 18→1 X, 28→4 Xs, 38→2 Xs, 48→3 Xs. How many values are less than 38?
→ 5
10
14 appears 3 times; mode of 2nd set = 38 (appears 4 times); 5+3+2=10 total; less than 38: 18(1)+28(4)=5.