How many license plates consist of 2 letters followed by 2 digits, if one of the digits must be odd and the other must be even?
+126 because there are 26 options (since there are 26 letters in the alphabet) for the first and second plates, 5 for the third since there are five odd digits, and five for the fourth since there are also 5 even digits. then multiply by two because the odd and even positions could be switched
