Hi there! I am Studyfin, your math buddy. Let's learn how to add and subtract fractions, even when they have different bottom numbers!
To add or subtract fractions, the bottom numbers must be the same. The bottom number is called the denominator. It tells us how many equal parts make up one whole shape.
When bottom numbers are different, we cannot add them yet. We must find a common denominator first. This means we change the fractions so they have the same bottom number.
Let us look at a real example. Imagine we want to add 1/2 of a pie and 1/4 of a pie. We can turn 1/2 into 2/4. Now we can add 2/4 and 1/4 to get 3/4 of a pie!
✏️ Worked example
Solve: 2/3 - 1/6
Find a common bottom number for 3 and 6. The number 6 works perfectly!
Change 2/3 so it has a 6 on the bottom. Multiply both top and bottom by 2. This gives us 4/6.
Now write the new math problem: 4/6 - 1/6.
Subtract the top numbers: 4 - 1 = 3. Keep the bottom number the same.
The answer is 3/6. We can simplify 3/6 by dividing top and bottom by 3 to get 1/2.
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