write 7 40 as a decimal number.

2 min read 23-02-2025

Writing fractions as decimals is a fundamental skill in mathematics. This article will guide you through the process of converting the mixed number 7 ⁴⁄₅ into its decimal equivalent. We'll break it down step-by-step, making it easy to understand and apply to other similar problems.

Understanding Mixed Numbers and Decimals

Before we begin, let's clarify what a mixed number and a decimal are:

Mixed Number: A mixed number combines a whole number and a fraction (e.g., 7 ⁴⁄₅).
Decimal: A decimal number uses a decimal point to separate the whole number part from the fractional part (e.g., 7.8).

Our goal is to represent the fractional part (⁴⁄₅) of the mixed number 7 ⁴⁄₅ as a decimal.

Converting the Fraction to a Decimal

The key to converting 7 ⁴⁄₅ to a decimal is understanding that a fraction represents division. The fraction ⁴⁄₅ means 4 divided by 5.

Perform the division: Divide 4 by 5. You can do this using long division or a calculator.
Result: 4 ÷ 5 = 0.8

Combining Whole Number and Decimal

Now that we've converted the fraction ⁴⁄₅ to its decimal equivalent (0.8), we can combine it with the whole number part of the mixed number (7).

Combine the parts: Simply place the decimal part (0.8) after the whole number (7).

Final Answer: 7.8

Therefore, 7 ⁴⁄₅ written as a decimal number is 7.8.

Practical Applications

Understanding how to convert fractions to decimals is crucial in many areas, including:

Everyday calculations: Dealing with money, measurements, and recipes often involves decimal numbers.
Science and engineering: Precision in scientific calculations requires the use of decimals.
Data analysis: Representing data in decimal form is essential for many statistical analyses.

Other Examples

Let's practice with a few more examples:

Example 1: Convert 3 ¹⁄₂ to a decimal. ¹⁄₂ = 0.5, so 3 ¹⁄₂ = 3.5
Example 2: Convert 1 ¹⁄₄ to a decimal. ¹⁄₄ = 0.25, so 1 ¹⁄₄ = 1.25
Example 3: Convert 5 ⅔ to a decimal. ⅔ ≈ 0.666..., so 5 ⅔ ≈ 5.666... (This is a repeating decimal)

Remember, the process always involves converting the fraction to a decimal by division, and then combining it with the whole number part. Practice makes perfect! Try converting different fractions to decimals to solidify your understanding.