We know that the last number on the second row is 5. What we need to know is how they got 5. We can...
The 8 on the first row is proportional to the 5 on the second row. For them to get 5 on the second row they multiplied the 8 by (5/8). I found that out by dividing the second number which was 8 by the first number which was 5.
So, 8 × (5/8) = 5. Since everything is proportional, we can multiply (5/8) to the other numbers on the first row to find out their numbers on the second row.
40 * (5/8) = 25
80 * (5/8) = 50
Those are the new numbers. If you have any questions then leave a comment. Good luck!