Open Middle®
Directions: Using the digits 1 to 5, at most one time each per number sentence, fill in the boxes to create two or more true number sentences.
Hint
What is the largest sum you could have?
What are the largest addends you could use?
What’s an example of addends you couldn’t use? Why not?
What are the largest addends you could use?
What’s an example of addends you couldn’t use? Why not?
Answer
There are many answers including:
1 + 2 = 3
1 + 3 = 4
1 + 4 = 5
etc.
Be sure to watch for students who use more than one number twice. Number tiles may be useful to prevent this.
Source: Robert Kaplinsky
The way I am reading this question, it sounds like we are to create two number sentences using only the digits 1-5 at most one time. Since there are three boxes in each sentence, we would need 6 unique digits, but we are only allowed to use up to 5 digits.
Would this be more explicit:
Directions: Use the digits 1 to 5, at most one time each per number sentence, to fill in the boxes to create two true number sentences.
Thank you for your suggestion. The question has been updated.