Open Middle®
Directions: Using the digits 1 to 9, at most one time each, find the largest possible area for the rectangle.
Hint
Which numbers would yield the largest area?
How can you find the area of a rectangle?
Where should you put the largest number? Why?
What will the rectangle with the largest area look like? (i.e. tall and skinny,…)
How can you find the area of a rectangle?
Where should you put the largest number? Why?
What will the rectangle with the largest area look like? (i.e. tall and skinny,…)
Answer
The area of the largest rectangle is 783 square units with the following dimensions: 9 x 87
Source: Nanette Johnson, Inspired by Mike Chamberlain’s Problem