Grade: Grade 2 Subject: Mathematics Unit: Measurement SAT: ProblemSolving+DataAnalysis ACT: Math

Centimeters and Meters

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Many countries around the world use centimeters and meters to measure length. These are called metric units. Scientists use them too!

What Is a Centimeter?

A centimeter is a small unit of length. It is about the width of your pinky fingernail.

We use the symbol cm for centimeters. Example: 5 cm

What Is a Meter?

A meter is a bigger unit of length. It is about the width of a door, or one big step.

We use the symbol m for meters. Example: 2 m

The Big Rule: 100 Centimeters = 1 Meter

This is very important to remember:

100 centimeters = 1 meter

A meter stick is 100 cm long!

When to Use Each Unit

  • Use centimeters for small things: pencils, erasers, your finger
  • Use meters for bigger things: rooms, playgrounds, buildings

Comparing to Inches and Feet

Here is how they compare:

  • 1 inch is about 2.5 centimeters
  • 1 meter is a little longer than 3 feet

Centimeters are smaller than inches!

Worked Examples

Example 1: Measuring with Centimeters

Problem: A crayon is 8 centimeters long. Is that more or less than 1 meter?

Step 1: Remember: 1 meter = 100 centimeters

Step 2: Compare: 8 cm and 100 cm

Step 3: 8 is much less than 100

Answer: 8 cm is much less than 1 meter

Example 2: Converting Meters to Centimeters

Problem: How many centimeters are in 2 meters?

Step 1: 1 meter = 100 centimeters

Step 2: 2 meters = 100 + 100 = 200 centimeters

Answer: 2 meters = 200 centimeters

Example 3: Choosing the Right Unit

Problem: Would you measure a swimming pool in centimeters or meters?

Step 1: Think about the size - a pool is big!

Step 2: Meters are better for big things

Answer: Measure a swimming pool in meters

Example 4: Adding Lengths

Problem: One piece of tape is 45 cm. Another is 55 cm. How long together?

Step 1: Add: 45 + 55 = 100 cm

Step 2: 100 cm = 1 meter

Answer: 100 cm or 1 meter

Example 5: Real World Measurement

Problem: A table is 3 meters long. How many centimeters is that?

Step 1: 1 meter = 100 centimeters

Step 2: 3 meters = 100 + 100 + 100 = 300 cm

Answer: 3 meters = 300 centimeters

Practice Problems

Try these problems on your own. Click "Show Answer" to check your work!

Problem 1: How many centimeters are in 1 meter?

Show Answer

100 centimeters

Problem 2: Is 150 cm more or less than 1 meter?

Show Answer

More (150 is greater than 100)

Problem 3: How many centimeters are in 4 meters?

Show Answer

400 centimeters (4 x 100 = 400)

Problem 4: Would you measure a paper clip in cm or meters?

Show Answer

Centimeters - A paper clip is small.

Problem 5: A book is 25 cm tall. How much more to make 1 meter?

Show Answer

75 cm (100 - 25 = 75)

Problem 6: Which is longer: 2 meters or 180 cm?

Show Answer

2 meters (2 m = 200 cm, which is more than 180 cm)

Problem 7: A jump rope is 5 meters long. How many cm is that?

Show Answer

500 centimeters (5 x 100 = 500)

Problem 8: Would you measure your classroom in cm or meters?

Show Answer

Meters - A classroom is big.

Problem 9: A rope is 300 cm. How many meters is that?

Show Answer

3 meters (300 / 100 = 3)

Problem 10: Which is longer: 1 meter or 90 cm?

Show Answer

1 meter (1 meter = 100 cm, which is more than 90)

Check Your Understanding

Question 1: What is the relationship between centimeters and meters?

Show Answer

100 centimeters = 1 meter. Centimeters are smaller units, and meters are bigger units.

Question 2: When should you use meters instead of centimeters?

Show Answer

Use meters for big things like rooms, fields, and distances. Use centimeters for small things like pencils and books.

Question 3: How many centimeters are in 5 meters?

Show Answer

500 centimeters (5 x 100 = 500)

Question 4: Which is smaller: a centimeter or an inch?

Show Answer

A centimeter is smaller. 1 inch is about 2.5 centimeters.

Next Steps

  • Practice: Find a ruler with centimeters and measure objects
  • Compare: Measure the same object in inches and centimeters
  • Challenge: How many centimeters tall are you?
  • Real Life: Look for metric measurements on packages and signs