Answer:
Leftmost 9: 900
9 between 9 and 0: 90
9 on left is worth 10 times 9 on right.
Explanation:
990.250
The 9 at the left is in the hundreds place, so it represents 9 hundreds, so its value is 900.
The 9 between the 9 and the 0 is in the tens place, so it represents 9 tens, and its value is 90.
Since the places are right next to each other, the 9 on the left is worth 10 times the 9 on the right. Sure enough, 900 is 10 times 90.