When adding or subtracting fractions, they should have the same denominator. In this exercise, we have two fractions with different denominators.
9 78 - 2 56
To create a common denominator, we will first find the least common denominator, LCD, of 8 and 6. To do it, we will write some multiples of 8 and 6 and find the smallest multiple that they both share.
Multiples of8:& 8, 16, 24, 32, 40, 48, 56, 64 ...
Multiples of6:& 6, 12, 18, 24, 30, 36, 42, 48, ...
We found that the LCD of 8 and 6 is 24. We can multiply both the numerator and denominator of 78 by 3 and the numerator and the denominator of 56 by 4 to create a common denominator.
