(5.2) and slope = -2/5 do you guys know the answer pls help

Table which ratio is equivalent to 3: 7? 6: 7 3: 21 24: 56 15: 30

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

What multiplys to be 1 but adds up to be 4