# Kilometer in Math

## Kilometer Definition

A kilometer is a very important unit of the metric system used to measure geographical distances and length.

1 kilometer to meter conversion is given as: 1 kilometer equals 1000 meters.

So, how long is a kilometer? When someone says they ran a total of 2500 meters during their morning walk, it means they covered 2.5 kilometers.

$1$ $\text{km} = 1000$ $\text{meters}$

$2.5$ $\text{km} \times 1000 = 2500$ $\text{meters}$

## What Is a Kilometer in Math?

Abbreviation of kilometer is ‘’km’’. Kilometer, or “km,” is a unit to measure length and distance. A kilometer is similar to the measuring the unit “mile,” which is also used to measure geographical distances. Many countries use kilometers as their standard unit of measuring length and distance.

1 kilometer is equal to 1000 meters. One thousand is a big number to write while measuring geographical distances and lengths. Hence, using a kilometer to measure the distance makes calculations much easier.

## Difference between Kilometers and Miles

Kilometer falls under the metric system of measurement, whereas mile falls under the imperial system of measurement. However, both “mile” and “kilometer” literally translate to “thousand” and are used to measure distance and length.

## Converting Kilometers

Conversions are required to understand and measure numerous components other than geographical distance and nautical miles.

For instance, in many countries, an individual’s height is measured in meters or centimeters, while the thickness of a notepad is measured using millimeters.

However, all these measuring units fall under the metric system. If you have numbers in one measuring unit, you can easily calculate others as well.

### Kilometers to Meters

As mentioned before, 1 kilometer (km) is equal to 1000 meters (m).

$1$ $\text{km} = 1000$ $\text{m}$

$2$ $\text{km} = 2000$ $\text{m}$

$3$ $\text{km} = 3000$ $\text{m}$

$4$ $\text{km} = 4000$ $\text{m}$

### Kilometers to Centimeters

1 meter (m) is equal to 100 centimeter (cm), which makes 1 kilometer (km) equal to 100,000 centimeters (cm).

$1$ $\text{km} = 1000$ $\text{m}$

$1$ $\text{m} = 100$ $\text{cm}$

$1$ $\text{km} = 1000$ $\text{m} = 1000 \times 100$ $\text{cm}$

$1$ $\text{km} = 1000$ $\text{m} \times 100 = 100,000$ cm

$2$ $\text{km} = 2000$ $\text{m} \times 200 = 200,000$ $\text{cm}$

### Kilometers to Millimeters

1 meter (m) is equal to 1000 millimeters (mm), which makes 1 kilometer (km) equal to 1,000,000 millimeters (mm).

$1$ $\text{km} = 1000$ $\text{m}$

$1$ $\text{m} = 1000$ $\text{mm}$

$1$ $\text{km} = 1000$ $\text{m} = 1000 \times 1000$ $\text{mm}$

$1$ $\text{km} = 1000$ $\text{m} \times 1000 = 1000000$ $\text{mm}$

$2$ $\text{km} = 2000$ $\text{m} \times 2000 = 2000000$ $\text{mm}$

### Kilometers to Miles

1 kilometer (km) equals 0.621371 miles (mi).

$1$ $\text{km} = 1000$ $\text{m}$

$1$ $\text{km} = 0.621371$ $\text{miles}$

$1$ $\text{m} = 0.000621371$

### Kilometer to Feet

1 kilometer (km) equals 3280.84 feet (ft).

$1$ $\text{km} = 1000$ $\text{m}$

$1$ $\text{km} = 3280.84$ $\text{ft}$

$1$ $\text{m} = 3.28084$ $\text{ft}$

## Conclusion

Do not worry if your child is struggling with the metric system. It can be a little confusing for young students to understand how long a kilometer is, how big a kilometer is, etc. It is common for students to get confused between kilometer, meter, centimeter, millimeter, etc.

Allow your child to spend time with the concepts to grasp them properly. Slowly and gradually, they will be able to learn about kilometers as a separate unit of the metric system as well as in tandem with others!

## Solved Examples

1. Two friends, Henry and Nicole, walk 1.5 kilometers to home every day from school. How many meters do they cover each day?

Solution: As we know, $1$ $\text{km} = 1000$ $\text{m}$

Hence, to calculate how many meters they cover each day, we can multiply 1.5 kilometers by 1000 meters (m).

$1.5$ $\text{km} \times 1000$ $\text{m} = 1500$ $\text{meter}$

Therefore, Henry and Nicole cover 1500 m every day.

2. Tony constructed a racetrack for her two toddlers, which is half a kilometer long. How long is the racetrack in centimeters (cm)?

Solution: As we know, $1$ $\text{km} = 100,000$ $\text{cm}$

Hence, to calculate the length of half kilometer racetrack in cm, we can divide:

$\frac{1}{2}$ $\text{km} = \frac{100,000}{2} = 50,000$ $\text{cm}$

Therefore, the length of the racetrack in cm is 50,000 cm.

3. Bruce is working on a new project 12 km away from his house. He drives to the new project site every day. How much distance does he drive every day in miles?

Solution: As we know, $1$ $\text{km} = 0.621371$ $\text{mi}$

To calculate how much distance he drives every day in miles, we can multiply,

$12$ $\text{km} 0.621371 = 7.45645$ $\text{miles}$

Therefore, Bruce drives 7.45645 miles every day.

4. Samantha is asked to convert the size of her notebook from millimeters to centimeters. If the notebook is 297 mm long, how long is it in cm?

Solution: As we all know, $1$ $\text{mm} = 0.1$ $\text{cm}$

To calculate the length of the notebook in cm, we can divide,

$297\div10 = 29.7$ $\text{cm}$

Therefore, the notebook is 29.7 cm long.

5. Leon and Rose decided to watch a movie together. Both drive to the movie theater from their house, covering 3.5 km respectively. How much distance do they cover combined in miles?

Solution: As we know, $1$ $\text{km} = 0.621371$ $\text{mi}$

$3.5$ $\text{km} \times 0.621371 = 2.1748$ $\text{mi}$

$2.1748$ $\text{mi} + 2.1748$ $\text {mi} = 4.3496$ $\text {mi}$

Therefore, combined, they both cover 4.3496 mi.

## Practice Problems

1

### The height of one floor of a building is 670 cm. If the building has 10 floors in total, what is the total height of the building in meters?

67 meters
70 meters
58 meters
65 meters
CorrectIncorrect
(As the number of total floors is 10, we multiply $670 \times 10$ and then convert it into meters by dividing the length value by 100.)
2

### Scarlet drives 7.5 km every day to work. How much distance does she cover every day in miles?

5.8 miles
5.0 miles
4.0 miles
4.6 miles
CorrectIncorrect
(To get the answer, divide 7.5 by 1.609 as 1 km is equal to 1.609)
3

### Which is longer, 2955 mm or 295 cm?

2955 mm
295 cm
Both are equal
None of the above
CorrectIncorrect
Correct answer is: Both are equal
(Convert 2955 mm to centimeter and then compare the result
$1$ $\text{cm} = 10$ $\text{mm}$
So $1$ $\text{mm} = 0.1$ $\text{cm}$
$2955$ $\text{mm} = 2955 \times 0.1 = 295.5$ $\text{cm}$
4

### Amanda’s height is 5 ft, whereas Felicia’s height is 185 cm. Who is taller?

Amanda
Felicia
Both are equal
None of the above
CorrectIncorrect
(Convert 185 cm into ft to know who is taller.)
5

### What unit of measurement will you use to measure your bed?

Centimeter
Kilometer
Mile
Gallon
CorrectIncorrect
(Kilometer and mile are used to measure geographical distances or large lengths, whereas gallon is used to measure volume.)