The decimal number 4.5 converts to the fraction 9/2.
To convert 4.5 into a fraction, recognize that 4.5 equals 4 plus 0.5. Since 0.5 is a common fraction, it can be written as 1/2. Multiplying 4 by 2 gives 8, and adding the numerator 1 results in 9, over the denominator 2. So, 4.5 equals 9/2.
What is 4.5 in Fraction?
The number 4.5, when expressed as a fraction, is 9/2. This is because 4.5 equals 4 and a half, which is equivalent to the fraction 1/2 added to 4 (or 8/2). By combining these, the total becomes 9/2, a simplified form of the decimal.
Conversion Tool
Result in fraction:
Conversion Formula
The conversion formula from decimal to fraction is: decimal = numerator/denominator. To find the fraction, multiply the decimal by a power of 10 to shift the decimal point, then simplify. For example, 4.5 times 10 is 45, so the fraction is 45/10, which reduced to 9/2.
This works because multiplying eliminates the decimal, and dividing numerator and denominator by their greatest common divisor simplifies the fraction.
Conversion Example
- Convert 3.75:
- Multiply 3.75 by 100 to get 375.
- Write as 375/100.
- Simplify by dividing numerator and denominator by 25: 375 ÷ 25 = 15, 100 ÷ 25 = 4.
- Answer: 15/4.
- Convert 2.25:
- Multiply 2.25 by 100: 225/100.
- Simplify by dividing by 25: 225 ÷ 25 = 9, 100 ÷ 25 = 4.
- Result: 9/4.
- Convert 5.125:
- Multiply 5.125 by 1000: 5125/1000.
- Simplify by dividing numerator and denominator by 125: 5125 ÷ 125 = 41, 1000 ÷ 125 = 8.
- Final fraction: 41/8.
Conversion Chart
This table shows decimal values from -20.5 to 29.5 and their corresponding simplified fractions. Use this chart to quickly see how decimals convert to fractions for common values.
| Decimal | Fraction |
|---|---|
| -20.5 | -41/2 |
| -19.5 | -39/2 |
| -18.5 | -37/2 |
| -17.5 | -35/2 |
| -16.5 | -33/2 |
| -15.5 | -31/2 |
| -14.5 | -29/2 |
| -13.5 | -27/2 |
| -12.5 | -25/2 |
| -11.5 | -23/2 |
| -10.5 | -21/2 |
| -9.5 | -19/2 |
| -8.5 | -17/2 |
| -7.5 | -15/2 |
| -6.5 | -13/2 |
| -5.5 | -11/2 |
| -4.5 | -9/2 |
| -3.5 | -7/2 |
| -2.5 | -5/2 |
| -1.5 | -3/2 |
| -0.5 | -1/2 |
| 0.5 | 1/2 |
| 1.5 | 3/2 |
| 2.5 | 5/2 |
| 3.5 | 7/2 |
| 4.5 | 9/2 |
| 5.5 | 11/2 |
| 6.5 | 13/2 |
| 7.5 | 15/2 |
| 8.5 | 17/2 |
| 9.5 | 19/2 |
| 10.5 | 21/2 |
| 11.5 | 23/2 |
| 12.5 | 25/2 |
| 13.5 | 27/2 |
| 14.5 | 29/2 |
| 15.5 | 31/2 |
| 16.5 | 33/2 |
| 17.5 | 35/2 |
| 18.5 | 37/2 |
| 19.5 | 39/2 |
| 20.5 | 41/2 |
| 21.5 | 43/2 |
| 22.5 | 45/2 |
| 23.5 | 47/2 |
| 24.5 | 49/2 |
| 25.5 | 51/2 |
| 26.5 | 53/2 |
| 27.5 | 55/2 |
| 28.5 | 57/2 |
| 29.5 | 59/2 |
Related Conversion Questions
- How to convert 4.5 into a mixed number instead of an improper fraction?
- What is the simplest form of the fraction for 4.5?
- Can 4.5 be written as a decimal in fraction form with different denominators?
- What are some common fractions equivalent to 4.5?
- How do I convert 4.5 to a percentage?
- Is 4.5 in fraction form the same as 9/2?
Conversion Definitions
Decimal: A number expressed using a decimal point to represent fractional parts of a whole, based on powers of ten, like 4.5 or -2.75, which are precise and easy to use in calculations.
Fraction: A mathematical expression representing a part of a whole, written as numerator over denominator (e.g., 9/2), that can be simplified or converted into decimal form for various calculations.
Conversion FAQs
What is the easiest way to convert 4.5 to a fraction?
The simplest method is to recognize 4.5 as 4 and 1/2. Convert 4 to 8/2, then add 1/2, resulting in 9/2. This avoids complex calculations, providing an accurate and easy way to express 4.5 as a fraction.
How do I reduce a fraction like 18/4 to its simplest form?
Find the greatest common divisor (GCD) of numerator and denominator, which is 2. Divide both by 2, reducing 18/4 to 9/2. Simplification makes the fraction easier to understand and use in calculations.
Can I convert 4.5 into a mixed number?
Yes, 4.5 is 4 and 1/2, which can be written as a mixed number 4 1/2. This form separates the whole part from the fractional part, often making the number more understandable in real-world contexts.
Is 4.5’s fraction form unique or are there alternatives?
While 9/2 is the simplest form, 4.5 can also be written as 18/4, 36/8, or 45/10, which are equivalent fractions. These can be useful in different situations but all represent the same value.
How can I convert 4.5 into a percentage?
Multiply 4.5 by 100 to get 450%. This way, you express the decimal as a percentage, which is useful for comparisons and calculations involving parts per hundred.