Operations with Fractions/ Decimals
Adding and Subtracting Fractions w/ Different Denominators
Step 2: Find the greatest common multiple. You do that by listing all the multiples of BOTH denominators.
Step 3: Multiply the numerator. If you multiplied the denominator by 4, you would also multiply the numerator by 4. Do that with both fractions.
Step 4: Add or subtract. You add or subtract the numerator, depending on the operation. You do NOT add or subtract the denominator.
Step 5: If it is improper, change it into a mixed number. If it is not in its simplest form, simplify it.
Adding and Subtracting Fractions w/ the Same Denominators
Step 2: Add the numerators.
Step 3: If it is improper, change it into a mixed number. If it is not in its simplest form, simplify it.
Example for Adding and Subtracting w/ Same Denominators
Example 2 for Adding and Subtracting w/ Same Denominators
Example for Adding and Subtracting w/ Different Denominators
Step 2: Multiply the numerator by the other fraction's numerator.
Step 3: Multiply the denominator by the other fraction's denominator.
Step 4: If the fraction is not in its simplest form or it is an improper fraction, you need to simplify to its simplest form or convert it into a mixed number.
Step 2: Keep the first fraction. You CANNOT keep the other fraction. You will get the incorrect answer.
Step 3: Change the division sign to a multiplication sign.
Step 4: Flip the numerator to the denominator's place, and the denominator to the numerator's place.
Step 5: Even though it's division, you need to multiply like in a multiplication problem with fractions.
Step 6: If the fraction is not in its simplest form or is an improper fraction, simplify it or change it into an improper fraction.
Adding With Decimals
Step 2 (OPTIONAL): Get rid of all the zeros at the very end of a decimal. Not if it was in the middle of a decimal, only the last digit.
Step 3: Bring your decimal down, right below where it was before.
Step 4: Add! Every number before the decimal, put before the decimal. Anything after the decimal, put after the decimal.
Step 5: If the last digit of the sum has a 0, you can get rid of the 0.
Adding Decimals Example
Adding With Decimals Example 2
Subtracting With Decimals
Step 2: Add a place holder if you need to.
Step 3: Bring your decimal straight down.
Step 4: Subtract like a normal subtraction problem. Any numbers before the decimal still go before the decimal, and any number after the decimal goes after the number.
Step 5: Get rid of any 0's at the very END of your number, not in the middle.
Example for Subtracting with Decimals
Video for Adding and Subtracting with Decimals
How to Multiply Decimals
Step 2: Multiply like a normal multiplication problem.
Step 3: Count how many digits there are after the decimal on BOTH decimals. That's how many digits you'll move your decimal over from the righthand side. If there is any space between one place value, add a 0.
Step 4: Get rid of any extra 0's in the product.
Example for Multiplying Decimals
Video for Multiplying Decimals
How to Divide Decimals
Step 2: You canNOT have you divisor a decimal, so you will push the decimal over 1 spot in the divisor AND dividend.
Step 3: Bring your decimal right above where it was.
Step 4: Do normal long division. If the number after the decimal in the dividend, put the number up after the decimal in the quotient. Same the other way around.
Step 5: Get rid of the very last 0 if you have one.