Answer: 3
Step-by-step explanation:
The numbers possible to begin with are 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 (18 options)
Making it only evens brings it down to 40, 42, 44, 46, 48, 50, 52, 54, 56 (9 options)
Then divisible by three leaves 42, 48, 54 (3 options)