Answer:
first digit: 9/18 = 0 and 9 left
second digit: 97/18 = 5 and 7 left
third digit: 72/18 = 4 and 0 left
fourth digit: 00 / 18 = 0 and 0 left
Answer is 540 (skipped the first 0).
Explanation:
Please note that you add another digit to what was left in the previous step.