I'm thinking of a number.
- if it is not a multiple of 4, then it is between 60 and 69
- if it is a multiple of 3 it is between 50 and 59
- if it is not a multiple of 6 it is between 70 and 79.
What is the number?
The solution to the problem is 76.
If not multiple of 4, must be : 61, 62, 63, 65,66,67,69
If multiple of 3 must be: 52, 52, 55,56,58
If not multiple of 6: 71, 73,74, 75,76,77
The following logic is applicable because the groups are exclusive of each other. This means that if the number is a member of one group, it cannot be a member of the others:
If multiple of 3, must be multiple of 6 and 4; impossible
If not a multiple of 4, must not be a multiple of 3, must be multiple of 6; impossible
If not a multiple of 6, must not be multiple of 3, must be multiple of 4; 76 is a member of the group that fits this.
Therefore the solution is 76.