The Number System

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to make the equation true. Source: Owen Kaplinsky

Directions: Using the integers -9 to 9, at most one time each, place an integer in each box to make the number line true. Note: The number line is not necessarily drawn to scale. Source: Amy Bloom

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to create a true statement. Source: Cecilia Calvo Pesce

Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to make the inequality true. Try to find solutions where the fractions are in their lowest terms. Source: Charlotte Hawthorne

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to make a true fraction division sentence. Source: Shanelia Rhome-Shannon and Aiden (Student)

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box and choose either multiplication/division or addition/subtraction to make the equation true. Source: Brian Errey

Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to make two different pairs of fractions that have a quotient of 2/3. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to make the inequality true. Source: Robert Millett

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to make the greatest possible product. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9, at most one time each, place a digit in each box to make the largest possible greatest common factor. Source: Howie Hua