[Maths Class Notes] on US Standard Length Pdf for Exam

Measurement is used to find a number that shows the size or amount of a quantity. Here, we will discuss the US standard system of measurement.

The most common unit of measurements:

Inches – An inch is a unit of length in the US customary systems of measurement. An inch was defined to be equivalent to exactly 25.4 millimeters in 1959.

Yard – A yard is a unit of length in both the imperial and US customary systems of measurement. In 1959, a yard was defined as exactly 0.9144 meters. It is also equal to 3 feet, or 36 inches.

Foot – A foot is a unit of length in the imperial and US customary systems of measurement. A foot is defined as exactly 0.3048 meters. 1 foot is equal to 12 inches.

Miles – A mile is a unit of length in the imperial and US customary systems of measurement. It is defined as 5,280 feet, 1,760 yards, or exactly 1,609.344 meters.

Inches to Yards

To convert an inch measurement to a yard, divide the length by the conversion ratio. We know that 1 yard is equal to 36 inches, so use this formula to convert.

Yards = inches ÷ 36

Ex- Convert 5 inches to yards.

Ans: As we know that 1 inch = 1/36 yard.

So, 5 inches = 5/36 = 0.138889 yard

Centimeters to Feet and Inches

To convert centimetres to feet and inches, first, divide the cm value by 30.48 to convert into feet. The integer part of the result will be feet value. After that to find the inch value, multiply the fractional part by 12.

Length Chart

US measurement system

uploaded soon)

For example:

5 yard  = 5 × 3 = 15 feet

144 inches  = 144 / 12 = 12 feet

Height Feet to Inches

To convert height from feet to inches, we should keep in mind the conversion ratio between 

1 foot is equal to 12 inches.

Ex-Convert 3 feet to inches.

Ans: As we know 1 feet = 12 inches.

So, 3 feet = 3 × 12 = 36 inches.

Standard Unit of Length

The standard unit of length is meter(m).

A meter length can be divided into 100 equal parts.

Each part is known as centimetre and written in short as ‘cm’.

Therefore, 1 m = 100 cm and 100 cm = 1 m

Miles to Kilometers

To convert from miles to kilometers we should use 1 mile is equivalent to  1.609344 kilometres.

Ex-Convert 5 miles to kilometres.

Sol: We know that 1 mile = 1.6093444 kilometres.

Hence 5 mile = 5 × 1.609344= 8.04672 km.

How Much is an Inch?

An inch is exactly 2.54 cm.

Yard to Inches

To convert a yard to an inch, multiply the length by the conversion ratio. 1 yard is equal to 36 inches, so use this simple formula to convert.

Inches = Yards × 36

Example- How to convert 5 yards to inches?

Ans: Here 1 yd = 36 inches

So, 5 yd = (5 × 36) = 180 inches

Did You Know?

• The word length comes from middle English ‘lengthe’ and from old English ‘lengou’ which means property of being long or extended in one direction.

• The metric system used for measuring length was first adopted in France and is currently used by around 95% of the world population.