Here are useful units of measure to know

Length
Metric System		English System
1 meter (m)	= 1000 millimeters (mm)	1 foot (ft)	= 12 inches (in)
1 meter (m)	= 100 centimeters (cm)	1 yard (yd)	= 3 feet or 36 inches
1 kilometer (km)	= 1000 meters (m)	1 mile (mi)	= 1760 yards or 5280 feet
1 centimeter (cm)	= 10 millimeters (mm)
	2.54 centimeters (cm)	= 1 inch (in)

Example 1: Unit conversion (English system)

Do the following conversions. Round to nearest tenth where necessary.
48 in = ft

We know that 1 foot (ft) = 12 inches (in) so

48 in × = × =  4 ft

So, 48 in = ft

Example 2: Unit conversion (metric system)

Do the following conversions. Round to nearest tenth where necessary.
5 cm = mm

We know that 1 centimeter (cm) = 10 millimeters (mm) so

5 cm × = × =  50 mm

So, 5 cm = mm

Example 3: Unit conversion (English and metric systems)

Do the following conversions. Round to nearest tenth where necessary.
2 m = ft

To convert between the two systems, we know that 1 centimeter (cm) = 2.54 inches (in).
There are multiple steps:   meters → centimeters → inches → feet

Step 1:  Convert meters (m) to centimeters (cm) by multiplying 100 cm / 1 m

2 m ×

Step 2:  Convert centimeters (cm) to inches (in) by multiplying 1 in / 2.54 cm

2 m × ×

Step 3:  Convert inches (in) to feet (ft) by multiplying 1 ft / 12 in

2 m × × ×

Step 4:  Solve the equation

2 m × × × =

2   m  × × × = 6.6 ft

So, 2 m = ft

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