Answer:
280
Step-by-step explanation:
We know that there are at least 8 regular subscribers and there are at least 9 premium subscribers. And we know it's in that ratio. So the best way to start this is to divide 595 by 8+9 to get the single unit amount of both subscribers:
595/17 = 35
So one unit of anything is at least 35. Now, since we're looking for regular subscribers, we'll multiply this value by 8:
35*8 = 280
So 280 is our answer!