If you would like to know the number that is greater than 8.604 but less than 8.643, you can look at the following numbers:
8.604 < 8.608 < 8.611 < 8.620 < 8.629 < 8.633 < 8.637 < 8.640 < 8.642 < 8.643
Result: All of the following numbers are greater than 8.604 and less than 8.643: 8.608, 8.611, 8.620, 8.629, 8.633, 8.637, 8.640, 8.642. You can choose one of them for example.