This math worksheet provides students with practice adding and subtracting fractions with unlike denominators. It contains two word problems asking students to find equivalent fractions with a common denominator and then add or subtract the numerators. The first problem asks what fraction of students are in eighth grade given that 1/3 are in sixth and 1/4 are in seventh. The second problem asks how much more crushed cookies Sarah needs given she has already crushed 1/10 of a cup.