Find all digits a (0–9) such that the three-digit number 5a2 is divisible by 3. Select all that apply.
Note
A number is divisible by 3 when the sum of its digits is divisible by 3; 5 + a + 2 = 7 + a, so a must make 7 + a a multiple of 3, which occurs for a = 2, 5, and 8.