How to convert 0.4 to a fraction?

0.4 = 4/10 Then simplify to 2/5.

0.4 terminating or repeating?

It is a terminating decimal. The simplest fraction is 2/5.

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0.4 =

0.4

(1 decimal place → denominator 10)

4/10

→ simplify ÷2

(divide numerator and denominator by 2)

Step 1: 0.4 has 1 decimal place, so write it as 4/10.

Step 2: Divide numerator and denominator by 2: 4/10 → 2/5.

Property: In simplest terms, denominators with prime factors only 2 and/or 5 produce terminating decimals.

Why can 0.4 be converted to a fraction?: Decimals can be expressed as fractions by using place value and simplifying.
0.4 terminating or repeating?: It is terminating.
Can it be simplified further?: 2/5 is simplest.

Percentage & Ratio: 0.4 can be interpreted as 2/5 in practical scenarios like discounts and rates.

Statistics: A proportion of 0.4 often represents a 40% probability — for example, a 40% significance level (p-value) in experiments or surveys.

Finance: Rates expressed with 0.4 (e.g., 40%) appear in returns and fees.