Open Middle®
Directions: Using the digits 0 to 9 at most one time each, place a digit in each box to make a true statement.
Hint
What numbers could you pick so that the numerator is a difference of squares?
Answer
3, 4, 2, 1 works. So does 4, 7, 5, 1.
Source: Julia Anker
5, 9, 3, 2 also works.
I assigned this to my class but excluded 0 as an available digit… it’s much more interesting without the 0….