Hey there!
Let's write all these numbers in order.
First, all numbers here are 4-digit numbers, except 1 (it's a 3-digit number)
So the smallest number is the 3-digit number.
399
Now, what's next?
let's check the thousands place (the first digit in the 4-digit numbers)
We see 3, 3, 4 and 4.
3 is smaller than 4.
Now we have 2 numbers: 3007 and 3333.
Well, which one's smaller? that's right, 3007.
So we have
399, 3007.
The third number is 3333 (the thousands place is 3)
so we have
399, 3007, 3333
Now, we have 2 numbers left, and they have a 4 in their thousands place.
The numbers are: 4011 and 4435.
Well, which one's smaller? that's right, 4011, and the greatest number is 4435.
Hence, we have
Hope everything is clear.
Let me know if you have any questions!
#LearningDoesn'tEnd
:-)