Line Plots — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A Grade 3 line plot of pencil lengths shows 2 Xs above 3 in, 3 above 3.5 in, 1 above 4 in. How many pencils in all?
A) 5 pencils
B) 6 pencils
C) 7 pencils
D) 8 pencils
Total pencils equals the sum of all Xs: 2 plus 3 plus 1 equals 6 pencils measured for the line plot.
2. On a Grade 3 line plot of leaf widths, 4 Xs are above 2.5 cm and 1 X is above 2 cm. How many more leaves are 2.5 cm than 2 cm?
A) 2 more
B) 3 more
C) 4 more
D) 5 more
Find how many more by subtracting columns: 4 Xs minus 1 X equals 3 more leaves at 2.5 cm than at 2 cm.
3. A Grade 3 line plot of crayon lengths uses Xs at 3, 3.5, 4, and 4.5 in. The mode is the value with the tallest stack. Which scale step is used between marks?
A) 1 inch
B) Half inch
C) Quarter inch
D) Two inches
The scale jumps by 0.5 each step, so the line plot uses half-inch units between each labeled scale mark.
4. A Grade 3 line plot uses values from 4 in to 5.5 in. What is the range of measurements shown?
A) 1 in
B) 1.5 in
C) 2 in
D) 0.5 in
Range equals largest minus smallest scale value used: 5.5 inches minus 4 inches equals 1.5 inches of range.
Part B: Fill in the Blank
Write the correct answer on each line.
1. A Grade 3 line plot uses inches from 2 in to 4 in by halves. The scale shows 2, 2.5, 3, 3.5, 4 inches.
The scale goes up by half-inch steps, so after 3.5 the next labeled mark is 4 inches on the line plot.
2. If a Grade 3 line plot has 2 Xs at 3 in, 4 Xs at 3.5 in, and 2 Xs at 4 in, the mode is 3.5 inches.
The mode is the value with the tallest column, and 4 Xs at 3.5 inches is taller than the 2 Xs at the other values.
3. A Grade 3 line plot of ribbons shows 5 Xs above 4.5 in. So 5 ribbons are 4.5 inches long.
Every X represents one ribbon, so 5 Xs above the value 4.5 inches means 5 ribbons measured 4.5 inches.
4. Tom measured pencils: 3, 3.5, 3.5, 4. To plot, he draws 2 X above 3.5 in on his Grade 3 line plot.
The value 3.5 appears two times in his data list, so Tom stacks 2 Xs above 3.5 inches on the line plot.
5. A Grade 3 line plot has 1 X each at 2, 2.5, 3, and 3.5 in. The total ribbons measured is 4.
Each of the four columns contains one X, so total Xs and total ribbons measured both equal 4 on the line plot.