Convert Decimals to Fractions
Step 1: Write out the decimal divided by 1.
Step 2: Safely remove the decimal point by multiplying both top and bottom by this magical number: a 1 followed by a 0 for every number in the decimal that is right of the decimal point.
Step 3: Reduce (simplify) the fraction
Example 1: Express 0.75 as a fraction
Step 1: write down:
0.75 |
---- |
1 |
Step 1: multiply both top and bottom by 100 (there were 2 digits after the decimal place so there should be a 1 and 2 zeros)
75 |
--- |
100 |
Step 3: Simplify Fraction:
| ÷25 |
|
75 |
| 3 |
---- | = | --- |
100 |
| 4 |
| ÷25 |
|
Answer = 3/4
Note: 75/100 is called a decimal fraction and 3/4 is called a common fraction!
Example 2: Express 0.625 as a fraction
Step 1: write down:
0.625 |
------- |
1 |
Step 1: multiply both top and bottom by 1,000 (there were 3 digits after the decimal place so there should be 3 zeros)
625 |
------ |
1,000 |
Step 3: Simplify Fraction:
| ÷25 |
| ÷5 |
|
625 |
| 25 |
| 5 |
------- | = | ---- | = | --- |
1,000 |
| 40 |
| 8 |
| ÷25 |
| ÷5 |
|
Answer = 5/8
Example 3: Express 0.333 as a fraction
Step 1: write down:
0.333 |
------- |
1 |
Step 1: multiply both top and bottom by 1,000 (there were 3 digits after the decimal place so there should be 3 zeros)
333 |
------ |
1,000 |
Step 3: Simplify Fraction:
Answer = 333/1,000
But a Special Note:
If you really meant 0.333... (in other words 3s repeating forever which is called 3 recurring) then we need to follow a special argument. In this case we would write down:
0.333... |
------- |
1 |
Then MULTIPLY both sides by 3:
| ×3 |
|
0.333... |
| 0.999... |
-------- | = | ------- |
1 |
| 3 |
| ×3 |
|
And 0.999... = 1 (Do you agree? See Our 9 Recurring discussion, so:
Answer = 1/3
Document Actions