What is the sum of 1/7, 2/7, and 4/7?

• A. 1
• B. 3/7
• C. 6/7
• D. 7/6

Answer: (A)

When you add fractions with the same denominator, you add the numerators and keep the denominator. Here all pieces are seventh-parts, so add 1, 2, and 4 to get 7, with the common denominator 7. That gives 7/7, which equals 1—a whole. The other values would require a different total of seventh-parts, so they don’t match the sum of these three pieces.