Answer:
The numbers would have to be 7, 8 and 1.
Explanation:
To find this, first note that 7 needs to be the middle number. So one will be greater and one smaller.
Next we know that the last two numbers must add up to 9. This is because after we subtract 7 from the total, we get 9.
Now since they need to equal 9 and be 7 apart, we can find that 8 and 1 are the only numbers that satisfy that stipulation.