First, I had to figure out the fourth digit by eliminating the numbers that we were not able to use to multiply by 3. For example, the numbers 0, 1, and 2 could not be the answer, because they were too small to use. This goes the same for 7,8,9 because they were too big to use and we already used 3, and you could only use each number once in this calculation. That now leaves us with 4, 5, and 6.
Next, we had to solve the third digit. Since 6+5=11 (Not possible) and 4+6=10(still not possible) the third digit must be 9 (because 4+5=9, which is possible because it is a single digit number. Consequently, the first fourth digits are 5694.
Next, we have to multiply 5694 with 3 to get the answer. The first, third and fifth digits are consecutive numbers, not in order.
5694
x 3
17082
The number 17082 is perfect because the first, third and fifth digits are 1,0,2 (not in order). You can rearrange them to make consecutive numbers:0,1,2. Therefore, this answer is correct.