Reading a Straight Edge

Created By:

Dr. A. Dávila

customary system

sistema tradicional

A common system of measurement used in the

United States.

La sistema de medición común utilizado en los Estados Unidos.

The distance between two points.

Es la distancia entre dos puntos.

lengthlongitud

A 12 mm

A decimal system of measurement based on the number ten. Meters, liters, grams, and the Celsius are some of the basic units of

measurement in this system.Una sistema decimal de medicíon

basado en el número diez. Metros, litros, gramos y centigrados son

algunas de las unidades básicas de medida en esta sistema.

metric systemsistema métrico

A standard measure of a quantity.

La medida estándar de una cantidad.

unitunidad

The International System (SI) basic unit for length or

distance.

La unidad de el Sistema Internacional (SI) de distancia o longitud.

meter (m)metro centimeter (cm)

centimetro

It measures 1/100 (0.01) of a meter.

Mide 1/100 (0.01) de un metro.

A fingernail is about 1

centimeter wide.

1 cm = 0.3937 in.

1 in. = 2.54 cm

millimeter (mm)milimetro

It measures 1/1000 (0.001) of a meter.

Mide 1/1000 (0.001) de un metro.

A dime is about one millimeter

thick.

Una moneda de 10¢ tiene una anchura aproximadmente un milimetro.

foot (ft)pie

It measures 12 inches.

Mide 12 pulgadas.

3 feet = 1 yard

The selected parts from a total number of equal parts which form a whole or a set.

El número que representa la partes seleccionadas de las partes iguales que forma un entero o elements en

el conjunto.

numeratornumerador

numeratornumerador

41p

inch (in.)pulgada

A unit of the customary system used to measure

length or distance.

Una unidad de la medición común que se utiliza para medir distancia o

longitud.

(1 pie)

1 inch(1 pulgada)

cm1 cm = 0.3937 in.

1 in. = 2.54 cm

part

The total number of parts that make a whole or a set.

El número total de partes que hacen un entero o un conjunto.

denominatordenominador

denominatordenominador

41

total equal parts per unit or setcantidad de partes iguales por unidad o

conjunto

Look at your straight edge closely to identify which system to use. For the customary

system, it might read in for inches or ft for feet. For the metric system, it might read cm

for centimeter or mm for millimeter.

Most straight edge rulers have an excess edge.

If it does have an excess edge, start measuring from the first mark.

Each number identifies a whole.

1 centimeter

Notice the longer line segment and its corresponding number.

whole centimeter

Notice the longer line segment and its corresponding number. This identifies the first whole centimeter.

whole centimeter

Count the number of spaces between each line segment. Each space represents a millimeter. How many millimeters make a whole centimeter?

fractions of a centimeter

Notice the first small line segment. This small line segment represents the first millimeter (on the meter side of a straight edge).

1 millimeters or 0.1 (1/10) of a cm

Notice the first small line segment. This small line segment represents the first millimeter (on the meter side of a straight edge).

2 millimeters or 0.2 (2/10 or 1/5) of a cm

Notice the first small line segment. This small line segment represents the first millimeter (on the meter side of a straight edge).

3 millimeters or 0.3 (3/10) of a cm

Notice the first small line segment. This small line segment represents the first millimeter (on the meter side of a straight edge).

4 millimeters or 0.4 (4/10 or 2/5) of a cm

Notice the first small line segment. This small line segment represents the first millimeter (on the meter side of a straight edge).

5 millimeters or 0.5 (5/10 or 1/2) of a cm

It takes 10 millimeters to make a whole centimeter.

one centimeterone millimeter

How many centimeters make a whole decimeter?

one decimeter

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

one decimeteris equal to 10 cm

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

1/10 (0.1) of a decimeter

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

2/10 or 1/5 (0.2) of a decimeter

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

3/10 (0.3) of a decimeter

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

4/10 or 2/5 (0.4) of a decimeter

It takes 10 centimeters to make a whole decimeter.

How many decimeters make a meter?

5/10 or 1/2 (0.5) of a decimeter

Count the number of spaces between each line segment. Each space represents a fraction of an inch. How many sections make a whole inch?

fractions of an inch

There are a total of 16 sections to a whole inch.

fractions of an inch

Notice the first small line segment. This small line segment represents the first fractional part of an inch.

1/16 which means 1 out of 16 sectionsor 0.0625 of an inch

2/16or 0.125 of an inch

Two fractional parts of an inch (2 out of 16 sections).

2/16 or 1/8 means (1 out of 8)or 0.125 of an inch

However, the every two sections can be combined for total of eight sections.

3/16 or 0.1875 of an inch

Three fractional parts of an inch (3 out of 16 sections).

4/16 or 0.25 of an inch

Four fractional parts of an inch (4 out of 16 sections).

However, two sections can be grouped for a total of eight sections.

4/16 or2/8 means (2 out of 8)0.25 of an inch

However, four sections can be grouped for a total of four sections.

4/16 or1/4 means (1 out of 4)0.25 of an inch

5/16 or 0.3125 of an inch

Five fractional parts of an inch (5 out of 16 sections).

6/16 or 0.375 of an inch

Six fractional parts of an inch (6 out of 16 sections).

6/16 or 3/80.375 of an inch

However, every two sections were paired for a total of 8 sections.

7/16 or 0.4375 of an inch

Seven fractional parts of an inch (7 out of 16 sections).

8/16 or 0.5 of an inch

Eight fractional parts of an inch (8 out of 16 sections).

8/16 or 4/80.5 of an inch

However, every two sections can be combined for a total of 8 sections.

8/16 or 2/4 means 2 out of 4 or0.5 of an inch

However, every four sections can be combined for a total of four sections.

8/16 or 1/2 means 1 out of 2 or0.5 of an inch

However, every eight sections can be combined for a total of 2 sections.

9/16 or 0.5625 of an inch

Nine fractional parts of an inch (9 out of 16 sections).

10/16 or 0.625 of an inch

Ten fractional parts of an inch (10 out of 16 sections).

10/16 or 5/80.625 of an inch

However, every two sections can be combined for a total of 8 sections.

11/16 or 0.6875 of an inch

Eleven fractional parts of an inch (11 out of 16 sections).

12/16 or 0.75 of an inch

Twelve fractional parts of an inch (12 out of 16 sections).

12/16 or 6/80.75 of an inch

However, every two sections can be combined for a total of 8 sections.

12/16 or 3/4 means 3 out of 4 or0.75 of an inch

However, every four sections can be combined for a total of four sections.

13/16 or 0.8125 of an inch

Thirteen fractional parts of an inch (13 out of 16 sections).

14/16 or 0.875 of an inch

Fourteen fractional parts of an inch (14 out of 16 sections).

14/16 or 7/80.875 of an inch

However, every two sections can be combined for a total of 8 sections.

15/16 or 0.9375 of an inch

Fifteen fractional parts of an inch (15 out of 16 sections).

16/16 or 1 whole inch

Sixteen fractional parts of an inch (16 out of 16 sections).

16/16 or 8/8 means 8 out of 81 whole inch

However, every two sections can be combined for a total of 8 sections.

16/16 or 4/4 means 4 out of 4 or1 whole inch

However, every four sections can be combined for a total of four sections.

16/16 or 2/2 means 2 out of 2 or1 whole inch

However, every eight sections can be combined for a total of 2 sections.

16/16 or 1/1 means 1 out of 1 or1 whole inch

All the sections form one whole inch