Grade 8

Directions: Using the digits 0 to 9 at most one time each, fill in the boxes twice to make two different true statements. You may reuse all the digits for each statement. Source: Robert Kaplinsky

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make a value that is as close to zero as possible without being exactly 0. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make the least possible value. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -8 to 8 at most one time each, place an integer in each box to make the greatest possible value. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the integers -9 to 9 at most one time each, place an integer in each box to make two values: one that is positive and one that is negative. You may reuse all the integers each time. Source: Robert Kaplinsky in Open Middle Math

Directions: Using the digits 1 to 9 at most twice each, make the sum of the four expressions the greatest possible value. Source: Catriona Shearer

Directions: Using the integers -9 to 9 (excluding 0) at most one time each, fill in the blanks to create two distinct perpendicular lines. Source: Louise Pepper with answers from the students of Kings College Alicante, Spain

Directions: Using the digits 1 to 9, at most one time each, fill in the boxes to make a product that equals 800,000,000. Source: Robert Kaplinsky

Directions: Given the point (3,5), use digits 1-9, at most one time, to find a point (__, __) that minimizes the slope of the line that passes through the two points. The slope cannot be undefined. Source: Nanette Johnson (Problem Based on Andrew Constantinescu’s Problem) and Andrew Constantinescu

Directions: Given the point (3,5), use digits 1-9, at most one time, to find a point (__, __) that maximizes the slope of the line that passes through the two points. The slope cannot be undefined. Source: Andrew Constantinescu