Directions: Use the digits 1-9, at most one time each, to create a true statement. Source: Andrew Stadel

Directions: Using the digits 1 to 9, at most one time each, fill in the boxes to create a true number sentence with the greatest possible value. Source: Robert Kaplinsky

Directions: Using the digits 1 to 9 at most one time each, fill in the boxes to make the smallest (or largest) difference. Source: Robert Kaplinsky

Directions: Using the digits 1 to 9 at most one time each, fill in the boxes to make the smallest (or largest) difference. Note: This problem’s difficulty can be adjusted by altering the number of digits (boxes), picking smallest or largest, or by picking either a positive, negative, or both. Source: Robert Kaplinsky

Directions: Using the digits 1 to 9 at most one time each, fill in the boxes to make the smallest (or largest) difference. Note: This problem’s difficulty can be adjusted by altering the number of digits (boxes), picking smallest or largest, or by picking either a positive, negative, or both. Source: Robert Kaplinsky

Directions: Find two fractions whose difference is 1/20. Source: Kara Colley

Source: Smarter Balance