Directions: Using the digits 0 to 9 at most one time each, fill in the boxes to create two unit rates. You may reuse all the digits each equation. Source: Robert Kaplinsky

Directions: Using the digits 1 through 9, at most one time each, place a digit in each box to create an equation with the greatest possible quotient. Source: Robert Kaplinsky

Directions: Using the digits 1 through 9, at most one time each, place a digit in each box to create two true equations: one where the quotient is greater than 40 and one where it’s less than 40. You may reuse the same digits for each of the equations. Source: Robert Kaplinsky

Directions: Using the digits 1 to 9 at most one time each, place a digit in each box to make a product that’s as close to 4/11 as possible. Source: Robert Kaplinsky

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

Directions: Using the digits 1 to 9 at most one time each, place a digit in each box to create a true statement. Source: Robert Kaplinsky

Directions: Using the digits 0 to 5 at most one time each, place a digit to create five fractions and place them all on a number line with the correct order and spacing. Source: Robert Kaplinsky

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 once each time, fill the boxes to make the greatest possible product. Source: Marc DeArmond

Directions: Using the digits 1 to 9, at most one time each, fill in the boxes to make a true statement. Source: Joseph Nguyen