Addition of Fractions
We multiply the top and the bottom of first fraction by 2
We have different denominators now (bottom numbers)
let's change the first fraction to have 4 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
1
2
x2
x2
+
1
4
=
4
2
+
4
1
=
We multiply the top and the bottom of first fraction by 2
We have different denominators now (bottom numbers)
let's change the first fraction to have 6 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
3
1
x2
x2
+
1
6
=
6
2
+
1
6
=
3
6
÷3
÷3
Simplify
fraction
=
We have the same denominators now (bottom numbers)
So we can add the fractions, add the tops and keepthe bottom number 4 without change.
4
1
+
3
4
=
4
but we know how much is 4 ÷ 4
=
We have the same denominators now (bottom numbers)
So we can add the fractions, add the tops and keepthe bottom number without change.
5
1
+
2
5
=
We multiply the top and the bottom of first fraction by 3
We have different denominators now (bottom numbers)
let's change the first fraction to have 6 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fraction. Add only tops!
We can only add fractions with the same bottoms, so
2
1
x3
x3
+
6
1
=
+
6
1
=
6
÷2
÷2
Simplify
fraction
=
We multiply the top and the bottom of first fraction by 3
We have different denominators now (bottom numbers)
let's change the first fraction to have 9 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
1
3
x3
x3
+
1
9
=
+
1
9
=
We multiply the top and the bottom of first fraction by 3
We have different denominators now (bottom numbers)
let's change the first fraction to have 15 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
1
5
x3
x3
+
15
1
=
+
15
1
=
We have the same denominators now (bottom numbers)
So we can add the fractions, add the tops and keepthe bottom number without change.
7
1
+
4
7
=
We multiply the top and the bottom of first fraction by 7
We have different denominators now (bottom numbers)
let's change the first fraction to have 21 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
1
3
x7
x7
+
21
1
=
+
21
1
=
We multiply the top and the bottom of first fraction by 3
We have different denominators now (bottom numbers)
let's change the first fraction to have 12 at the bottom
Now we have the same numbers at the bottoms, sowe can add the fractions. Add only tops!
We can only add fractions with the same bottoms, so
4
1
x3
x3
+
12
1
=
+
12
1
=
12
÷4
Simplify
fraction
÷4
=
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