Answer:

In order to add 1/4 and 2/3 it is necessary to rewrite the fractions so that the bottom numbers (the denominators) are the same. In this case, since 12 is the smallest number which is 4 and 3 divide into, the fractions can be rewritten as twelfths. 12 is the common denominator

1/4 = 3/12 and 2/3 = 8/12
Then 1/4 + 2/3 = 3/12 + 8/12 = 11/12