Speedway: Add & Subtract Fractions

Solve the given fraction equation. Then click on the correct answer to move your car along the track. The quicker you answer, the faster your car moves. Try to be the first one across the finish line!

Adding Fractions

Step #1 – Make sure the denominators are the same: If the fractions you’re adding have different denominators, you need to find a common denominator. To do this, you can either find the least common multiple (LCM) of the denominators or simply multiply the denominators together. Once you have a common denominator, proceed to the next step.

Step #2 – Add the numerators: Once the denominators are the same, you can add the numerators together. Simply add the numbers on top of the fraction (the numerators) to get the new numerator of the resulting fraction.

Step #3 – Keep the denominator the same: The denominator of the resulting fraction remains the same as the common denominator you found or started with.

Step #4 – Simplify (if necessary): After adding the numerators, you may need to simplify the resulting fraction by finding the greatest common divisor (GCD) of the numerator and denominator and dividing both by it. This step is not always necessary but can make the fraction easier to work with.

Example: 1/3 + 2/5

Step 1: Find the common denominator.

The common denominator for 3 and 5 is 15 (the least common multiple of 3 and 5).

Step 2: Add the numerators.

1 + 2 = 3

Step 3: Keep the denominator the same.

The denominator remains 15.

1/3 + 2/5 = 3/15

Step 4: Simplify (if necessary)

3/15 = 1/5

Subtracting Fractions

Step #1 – Make sure the denominators are the same: Like adding fractions, you need to have the same denominator for the fractions you’re subtracting. If the denominators are different, find a common denominator by either finding the least common multiple (LCM) of the denominators or simply multiplying the denominators together.

Step #2 – Subtract the numerators: Once you have the same denominator for both fractions, subtract the numerators. Simply subtract the top numbers (numerators) of the fractions to find the new numerator of the resulting fraction.

Step #3 – Keep the denominator the same: The denominator of the resulting fraction remains the same as the common denominator you found or started with.

Step #4 – Simplify (if necessary): After subtracting the numerators, you may need to simplify the resulting fraction by finding the greatest common divisor (GCD) of the numerator and denominator and dividing both by it.

Example: 3/4 – 5/8 =

Step 1: Find the common denominator.

The common denominator for 4 and 8 is 8 (the least common multiple of 4 and 8).

Step 2: Convert fractions to same denominator:

6/8 – 5/8

Step 3: Subtract the numerators.

6 – 5 = 1

Step 4: Keep the denominator the same.

The denominator remains 8.

3/4 – 5/8 = 1/8