Skill: Create line plots

A line plot shows where each measurement belongs on a number line.

1. Find the smallest and largest measurements.
2. Choose an equally spaced scale that includes every measurement.
3. Place one mark, such as $X$, above the number for each measurement.
4. Stack marks when measurements are repeated.

Suppose these are the lengths of seven objects, in inches:

$$\frac14,\ \frac12,\ \frac12,\ \frac34,\ 1,\ \frac14,\ 1\frac14$$

The measurements use fourths, so make the number line go up by $\frac14$. To keep the spaces equal, label the points as fourths:

$$0,\ \frac14,\ \frac24,\ \frac34,\ \frac44,\ \frac54$$

Remember that $\frac24=\frac12$, $\frac44=1$, and $\frac54=1\frac14$.

Now place the marks:

• There are two measurements of $\frac14$, so place two $X$'s there.
• There are two measurements of $\frac24$, so place two $X$'s there.
• Place one $X$ at each of $\frac34$, $\frac44$, and $\frac54$.

                 X
         X       X
         X       X       X       X       X
         |-------|-------|-------|-------|-------|
         0      1/4     2/4     3/4     4/4     5/4

The line plot has $7$ marks altogether, matching the $7$ measurements. Repeated measurements are shown by stacking marks above the same location.