Question

Problem 1. Your company is creating product code for its product control. They need you to figure out some stuff

If the code consists of 3 small letters from our English alphabet followed by a dash, and then 4 numbers followed by a dash and then followed by 2 letters (again small English alphabet), please answer the following important cooperate questions . _ _ _ - _ _ _ _ - _ _ (a) How many different product codes are there if there are no restrictions? (b) How many product codes are there if the initial 3 letter section must all distinct vowels and the first number in the number part must be a 3 or a 7 and the final 2 letters must be different.

Answer 1