Answer:
15.
16.
17.
Step-by-step explanation:
<u>In order to add or subtract two fractions with different denominators more easily, find the LCM of the denominators and solve by adding or subtracting the numerator.</u>
<em>LCM - Lowest Common Multiple</em>
The lowest common multiple is the number that shows up earliest that is in both numbers' multiples.
Example: LCM of 2 and 3
2, 4, 6, 8, 10...
3, 6, 9, 12, 15...
Because 6 is the number that shows in both sets first, 6 is the LCM.
<u>We will use this process to solve each problem:</u>
<u>15:</u>
+ Because the denominators are the same, adding can be done immediately.
To put this into simplest form, divide by .
÷ Divide.
<u>16:</u>
+ The LCM of 5 and 6 is 30. So, multiply by and by .
× + × Multiply.
+ Add the fractions.
Because 37 is a prime number, this is the simplest form.
<u>17:</u>
- The LCM of 6 and 9 is 18. So, multiply by and by .
× - × Multiply.
- Subtract the fractions.
Because 7 is a prime number, this is the simplest form.