What is 1/8 plus 7/8?

• A. 1/8
• B. 7/8
• C. 1
• D. 9/8

Answer: (C)

When adding fractions with the same denominator, you add the numerators and keep the denominator. Here, both fractions share 8 as the bottom number, so add 1 and 7 to get 8 over 8. Since 8/8 equals 1, the sum is 1.

Think of a whole split into 8 equal parts: one part plus seven parts makes all eight parts, which is the whole.

The other possibilities would represent only part of the whole (one part or seven parts) or more than a whole (nine parts), which isn’t the total you get by combining these two fractions.