Search form

Deciphering Decimals - Real-World Applications

Grade: 6-8th Grade

Duration: 55 minutes

Objective

By the end of this lesson, your students will understand decimals and their real-world applications, including money, measurements, and data analysis.

Materials Needed

  • Whiteboard and markers

  • Real-life examples of decimals (e.g., money, measurements)

  • Paper and pencils for students to attempt practice answers

Introduction (5 minutes)

Let's start with a question: Why are decimals important? Wait for a few students to respond, and then continue.

Today, we will explore how decimals are used in the real world.

Activity 1: Decimals Demystified (10 minutes)

First, let me explain decimals. Imagine you have a pizza and want to share it with three friends. But one friend only wants half of their slice. How do we deal with that? Decimals come to the rescue. We'll represent that half slice as 0.5. 

Write some decimal numbers on the board and discuss what each one represents. Use examples like 0.25 (1/4), 0.75 (3/4), and 0.50 (1/2). Explain how decimals are like fractions but are easier to work with when dealing with parts of a whole.

Activity 2: Real-World Applications (15 minutes)

Now that we've covered the basics, where do decimals appear in real life? Wait for a few students to respond.

  • Use money as an example, like $5.75 or $8.50. Discuss how decimals help us count our cash accurately. 

  • Use measurement as an example, such as 2.5 yards or 3.75 liters. Discuss how decimals make it easier to be precise.

Activity 3: Let's Crunch Some Numbers (20 minutes)

It's time to test our decimal skills. Here are several practice examples involving decimals. Let's first learn how to add and subtract decimals, then multiply and divide, and finally answer some real-world problems.

Allow students to work in pairs or on whiteboards.

Decimal Practice

Instructions: Solve the following problems involving decimals. Show your work and write your answers in the space provided.

1. Add the following decimals:

  1. 3.25 + 2.14 =

  2. 6.87 + 4.92 =

  3. 0.75 + 1.25 =

2. Subtract the following decimals:

  1. 5.67 - 3.42 =

  2. 8.50 - 2.75 =

  3. 12.34 - 6.78 =

3. Multiply the following decimals:

  1. 2.5 × 1.2 =

  2. 3.4 × 0.5 =

  3. 0.75 × 0.25 =

4. Divide the following decimals:

  1. 9.6 ÷ 2 =

  2. 7.5 ÷ 3 =

  3. 4.8 ÷ 0.4 =

5. Solve the word problems:

  1. Sarah bought 2.75 yards of fabric. She used 1.5 yards to make a dress. How much fabric does she have left?

  2. A pizza has been divided into 8 equal slices. If Emma eats 2.25 slices and Liam eats 1.75 slices, how many slices are left?

  3. There are 24 students in a class. Each student receives $3.50 for completing a survey. How much money will the class receive in total?

  4. Sarah spent $12.50 on lunch and $8.75 on a movie ticket. How much money did she spend in total?

  5. A recipe calls for 2.25 cups of flour, but you only have 1.5 cups. How much more flour do you need to complete the recipe?

  6. Alex ran 3.5 miles on Monday, 2.25 miles on Tuesday, and 4.75 miles on Wednesday. How many miles did he run in total?

  7. A bottle of juice contains 0.75 liters. If you drink half of the bottle, how much juice do you have left?

Answers

1. 

  1. 5.39

  2. 11.79

  3. 2.00

2.

  1. 2.25

  2. 5.75

  3. 5.56

3.

  1. 3.0

  2. 1.7

  3. 0.1875

4.

  1. 4.8

  2. 2.5

  3. 12.0

5. 

  1. 1.25 meters

  2. 4 slices

  3. $84.00

  4. $21.25

  5. 0.75 cups

  6. 10.5 miles

  7. 0.375 liters

Lesson Conclusion (5 minutes)

We've cracked the code on decimals and discovered their importance in our daily lives. Decimals are everywhere, whether divvying up pizza slices or counting our pocket change.

Homework: Decimals in My Life

Instructions: Your homework assignment is to find three examples of decimals in your life. Decimals are all around us, so see where you can spot them. Write down 3 examples and briefly explain what the decimal represents.

Bonus Challenge: Can you think of a creative way to represent each decimal example? Draw a picture or write a short story illustrating how decimals are used daily.

Written by Brooke Lektorich
Education World Contributor
Copyright© 2024 Education World