Write all possible 3-digit numbers that can be formed by the digits 9, 2 and 0, using each digit only once in each number.

When forming 3-digit numbers using the digits 9, 2, and 0, with each digit used only once, we must remember that a 3-digit number cannot start with 0.

If the hundreds digit is 9 : the remaining digits are 2 and 0.

Possible numbers: 920, 902

If the hundreds digit is 2 : the remaining digits are 9 and 0.

Possible numbers: 290, 209

Hence, the possible 3-digit numbers are 920, 902, 290, 209.