Free interactive math game: Complete the Whole — 3/7 + ? = 1. Part of the Fractions category on MathKite.
Taken from the generator that powers this exercise. A fresh set appears every time the page is opened, and the printable worksheet holds ten of them.
Finding the fraction needed to complete a whole.
Subtract the fraction from one, written with the same denominator.
Three eighths plus five eighths makes eight eighths, so the missing piece is five eighths.
Subtracting from the denominator alone. The whole is the denominator over itself, such as 8 over 8.