## Unit Conversions Length

#### Unit Conversions – Length and Area

Look at the table below and memorize the metric conversions of all units used to measure length.

10 mm = 1 cm

100 cm = 1 m

1,000 m = 1 km

In order to convert metric units into English units and other units of measurements, we will use the
conversion factors stated above. Notice that we always use 1 unit of the length to be converted. Once this
is known, the conversion factor, we can then use this to multiply against a unit we wish to be converted.

#### REMEMBER

When going from a large unit to a small unit, you multiply.

When going from a small unit to a large unit, you divide.

There is another way of converting units. It is often called the long way because you need to arrange the
values to make a ratio and proportion equation. For example:

1.    If the distance between Jamie's and Sandra's house is 13 km, how many miles apart are they from each other?

8.06 km

1 km = 0.62 miles

(1km / 0.62 mi) = (13km / x)

0.62 x 13 = x

X = 8.06 km

2.   Eric Dickerson is an American footballer who holds the record for the most rushing yards per season in
1984. His number is 2,104 yards. How many meters in total did he run in the 1984 season?

1914.64 m

Convert yards to meters

(1 yd / 0.91 m) = (2104 / x)

2104 x 0.91 = x

1914.64 m = x

3.   Nora is a marathon athlete who trains everyday except weekends by running 15 miles along the coast.
What is the total distance she covers weekly in km?

24.2 km

Convert miles to km

(1 km / 0.62 mi) = (x / 15)

15 / 0.62 = x

24.2 km = x

#### Try these questions

1.   Jessie travels 40 miles daily to get to her workplace from her home. How many kilometers away is her
workplace from her home?

Explanation:

Use the conversion factor stated in the table above:

1 km = 0.62 miles

X km = 40 miles

0.62 miles x 40 miles = 24.8 km

2.    Flora is 55 cm taller than Mara who is 5'6 feet. What is Flora's height in cm?

Explanation:

First, convert 5ft 6 inches (Mara's height) into cm:

5ft = 152.40 cm

1 inch = 2.54 cm; 6 x 2.54 = 15.24 cm

152.4 cm + 15.24 cm = 167.64 cm

Flora is 55 cm taller than Mara's 167.64 cm height.

Therefore,

Flora's height is: 167.64 + 55 cm = 222.64 cm

3.   A doghouse measures 3ft length and 5ft breadth.

1.   What is the area of the doghouse in ft? (Area = length x breadth) MM

Explanation: 3 ft x 5 ft = 15 ft2

2.   What is the area of the doghouse in m?

Explanation:

Convert ft to meters

1 ft = 0.30 m

15 ft2 x 0.30 m = 4.5 m2

4.    Gabby spends the morning in a playroom that is 4 meters long and 10 meters wide. What is the area of
the floor in the room? (Area = length x width)