What is 0.4 as a fraction?

Converting decimals to fractions can be useful in many situations. Let's go through the steps to convert a decimal 0.4 to a fraction.

You can try other values to get more familiar with the conversion process.

Often, convert 0.395 to a fraction or 0.405 to a fraction, depending on the task.

Understanding the decimal: “0.4”

A decimal number consists of an integer part and a fractional part, separated by a decimal point. The integer part is on the left, and the fractional part is on the right. For example, in 0.4, 0 is the integer part and 4 is the fractional part.

Conversion Explanation:

  1. For the numerator:
    • We start with the number 0.4.
    • By removing the decimal point, we derive the numerator as 4.
  2. For the denominator:
    • Each position after the decimal represents a division by 10.
    • Thus, having 1 positions after the decimal equates to 10 or 101.
  3. Factors:
    • The factors for the numerator and the denominator are numbers that can evenly divide each of them.
    • For instance, the factors of 4 include 1, 2, and 4.
    • The factors of 10 comprise 1, 2, 5, and 10.
  4. Greatest Common Divisor (GCD):
    • It's the largest number that can evenly divide both the numerator and the denominator.
    • In this instance, the GCD for 4 and 10 is 2.

The factors of 4 are:

1 2 4

The factors of 10 are:

1 2 5 10

Conversion formula (equation):

0.4=0.41=0.4 × 101 × 10=410=4÷210÷2=25

Solution:

0.4 = 25

What is a decimal?

A decimal is a numeral system that includes a point to separate the whole number part from the fractional part. This system makes it easy to work with numbers less than one.

What is a fraction?

A fraction is a mathematical way of showing a part of a whole. It has two parts: the numerator on top and the denominator below, which help express partial values and comparisons.

Step-by-step solution:

  • Step 1: First, write the decimal as a fraction over 1. This sets up the next steps. 0.4 = 0.41
  • Step 2: Decimals can have different lengths. We will align the number of digits after the decimal point. For 0.4, we have three digits. This means multiplying the fraction by a factor of 10 for each digit. Factor = 101 = 10
  • Step 3: Using this factor, multiply both the numerator and the denominator. 0.4 × 101 × 10 = 410
  • Step 4: Now we need to simplify the fraction by finding common divisors. The greatest common divisor is 2. Divide both the numerator and the denominator by this common divisor. 4 ÷ 210 ÷ 2 = 25

Answer in mixed fraction format:

0.4 =
2
5