“Working with Fractions” A Review of Addition and Subtraction CLICK HERE TO BEGIN

Goals: After finishing this activity you will be able to: Add fractions with like denominators Add fractions with like denominators Add fractions with unlike denominators Add fractions with unlike denominators Subtract fractions with like denominators Subtract fractions with like denominators Subtract fractions with unlike denominators Subtract fractions with unlike denominators Click to CONTINUE

Fractions Let’s review the parts of a fraction: Numerator Denominator Fractions have “Like Denominators” if both fractions have the exact same number in the denominator. Fractions have “Unlike Denominators” if they have different numbers in the denominator. Example Click to CONTINUE

“Like Denominators” The same number for both fractions RETURN to Lesson

“Unlike Denominators” Different numbers for each fraction RETURN to Lesson

Adding Fractions with LIKE Denominators Let’s say we wanted to solve the problem below: Since these fractions have the same number in the denominator, all we have to do is add the numerators! WATCH it happen!

When adding fractions DO NOT add the denominators together! Click to CONTINUE

Adding Fractions with UNLIKE Denominators This time, let’s try to solve a problem that is slightly more challenging: Since the denominators are NOT THE SAME, the first thing we have to do is make them the same by finding the Least Common Multiple or the LCM. Click here to FIND the LCM.

Step #1: List the multiples of each denominator. Step #2: Find the SMALLEST number that is in BOTH lists. This number is the LCM of the denominators! Click here to find out what to do now that we have the LCM!

We want to make the denominators of both fractions to be equal to the LCM we just found. We can use multiplication to make that happen! Now that we have like denominators we can add the fractions like we did last time!

Click to CONTINUE

Subtracting Fractions with LIKE Denominators Let’s say we wanted to solve the problem below: Since these fractions have the same number in the denominator, all we have to do is subtract the numerators! WATCH it happen!

When subtracting fractions DO NOT subtract the denominators! Click to CONTINUE

Subtracting Fractions with UNLIKE Denominators This time, let’s try to solve a problem that is slightly more challenging: Since the denominators are NOT THE SAME, the first thing we have to do is make them the same by finding the Least Common Multiple or the LCM. Click here to FIND the LCM.

Step #1: List the multiples of each denominator. Step #2: Find the SMALLEST number that is in BOTH lists. This number is the LCM of the denominators! Click here to find out what to do now that we have the LCM!

We want to make the denominators of both fractions to be equal to the LCM we just found. We can use multiplication to make that happen! Now that we have like denominators we can add the fractions like we did last time!

Click to CONTINUE

Let’s Review: To Add or Subtract fractions with “Like Denominators:” all you have to do is add or subtract the numerators. To Add or Subtract fractions with “Unlike Denominators:” First find the LCM of the denominators. First find the LCM of the denominators. Second, multiply each fraction on make the denominators equal to the LCM Second, multiply each fraction on make the denominators equal to the LCM Finally, add or subtract the numerators Finally, add or subtract the numerators Time to PRACTICE

Problem #1 Click on the letter of the correct answer: A.) 11 7 B.) 22 7 C.)

That is Correct! Go to Problem #2

Sorry that is Incorrect… Remember, when adding fractions with the same denominator:  Add the numerators  DO NOT add the denominators  Simplify the fraction when needed Go to Problem #2

Problem #2 Click on the letter of the correct answer: 12 7 A.) 35 7 B.) C.)

That is Correct! Go to Problem #3

Sorry that is Incorrect… Remember, when adding fractions with the different denominators:  Find the LCM of the denominators  Use multiplication to change the denominators  Add the “new” numerators, but NOT the “new” denominators Go to Problem #3

Problem #3 Click on the letter of the correct answer: 0 8 A.) B.) 21 8 C.)

That is Correct! Go to Problem #4

Sorry that is Incorrect… Remember, when subtracting fractions with the same denominator:  Subtract the numerators  DO NOT subtract the denominators  Simplify the fraction when needed  You can NEVER have a zero in the denominator! Go to Problem #4

Problem #4 Click on the letter of the correct answer: 55 3 A.) 6 3 B.) C.)

That is Correct! Click here to FINISH this lesson

Sorry that is Incorrect… Remember, when subtracting fractions with the different denominators:  Find the LCM of the denominators  Use multiplication to change the denominators  Subtract the “new” numerators, but NOT the “new” denominators Click here to FINISH this lesson

Congratulations! You have finished this review lesson. Please see your teacher to receive your homework assignment where you will practice these skills. Please see your teacher to receive your homework assignment where you will practice these skills.