Answer:
x ≤ 10, x ≥ 12
Explanation:
Let x = the missing number
Because a number minus one is 9 or less, that number cannot be bigger than 10. Therefore, it can be simplified to:
For the next one:
This expression can be simplified as:
This is because if two times a number is at least 24, that number cannot be bigger than 12.
Therefore, the equations you can use are listed above.