Use a system of linear equations to determine the solution. Use a calculator where appropriate. The difference of two integers is 30. Determine the two numbers if the larger is 3 less than four times the smaller.

Suppose you are choosing a 6-digit personal access code. this code is made up of 4 digits chosen from 1 to 9, followed by 2 letters chosen from a to z. any of these digits or letters can be repeated. find the total number of personal access codes that can be formed. 492,804 341,172 39,917,124 4,435,236