Open Middle®
Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to and make the greatest/least product.
Hint
Which numbers should we use? Which numbers should we not use?
Answer
Greatest: (9-2)(8-1)
Source: Nanette Johnson
Smallest:
Subtract the numbers that are next to each other. That will get you to the product of 1.
Example: (9-8)(7-6) = 1×1=1
Least: from Srihaas A in Mrs. Kinney’s Class (9-2) (1-8) = -49
Least:
(1-9)(8-2) = -56
(1-9)(8-2)=56
(9-8)
(7-1)
(5-4) x (3-2) = 1×1=1