To a prime number bigger than 2, 1 is added, the result is multiplied by three. What can be the result of these actions?
A seven-digit phone number is divisible by 3. After adding the two digits of the area code the number is not divisible by 3, which of the following cannot be the area code?
In a Greek restaurant there is a custom to break plates during celebrations. If after 8 celebrations there were only 6 plates left, which of the following could be the original number of plates before the celebrations?