Measure Lengths and Line Plots
Aligned to 3.MD.B.4 — Common Core State Standards for Mathematics.
What this lesson teaches
You can measure lengths to the nearest half inch or fourth inch with a ruler. A line plot uses an X above a number to show each measurement.
Worked examples
Example 1
You measure 3 pencils: 4 inches, 4 and 1/2 inches, and 4 inches. On a line plot, put two X marks above 4 and one X mark above 4 and 1/2.
Example 2
You measure 4 ribbons: 2, 2 1/2, 3, and 3 inches. The line plot gets one X above 2, one above 2 1/2, and two above 3.
Example 3
The line plot shows the shape of the data at a glance: the tallest stack of X's is the length that happened most often.
Practice questions
- Measure a crayon to the nearest 1/2 inch.
- On a line plot, 3 leaves are 2 inches long. How many X marks go above 2?
- What does each X on a line plot stand for?
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Medir Longitudes y Diagramas de Puntos
Puedes medir longitudes a la media pulgada o al cuarto de pulgada más cercano con una regla. Un diagrama de puntos usa una X encima de un número para mostrar cada medida.
Ejemplo 1: Mides 3 lápices: 4 pulgadas, 4 y 1/2 pulgadas, y 4 pulgadas. En el diagrama de puntos, pon dos X encima del 4 y una X encima del 4 y 1/2.
Ejemplo 2: Mides 4 listones: 2, 2 1/2, 3 y 3 pulgadas. El diagrama recibe una X encima del 2, una encima del 2 1/2 y dos encima del 3.
Ejemplo 3: El diagrama de puntos muestra la forma de los datos de un vistazo: la torre más alta de X es el largo que se repitió más.
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