Open Middle®
Directions: Using the digits 0 through 9 at most one time each, place a digit in each box to make a two-digit number that has a value between given numbers.
Hint
Can you decompose the numbers into bundles of tens and ones? What tools could you use?
Answer
There are many solutions including:
12, 35, 40, 41, 56, 78, 88, 93, 107
21, 35, 40, 41, 53, 78, 88, 96, 107
12, 35, 40, 41, 56, 78, 88, 93, 107
21, 35, 40, 41, 53, 78, 88, 96, 107
Source: Thach-Thao Phan
This is an excellent problem for ordering numbers, challenging students to do deeper thinking, where they might conclude through their efforts, that there is more than one correct answer.
I agree. Thank your for sharing
20,35,37,41,45,76,88,89,107