1
+
9
4
Since these fractions have different denominators, we need to find the least common multiple of the denominators
The least common multiple of 2 and 9 is 18, so we need to multiply to make each of the denominators = 18
2
1
∗
9
9
=
18
9
9
4
∗
2
2
=
18
8
Since these fractions have the same denominator, we can just add the numerators
18
9
+
18
8
=
18
17
