Answer:
.98 L / b * .4 b = .392 L amount contained in sample
.99 L / b * .25 b = .248 L this was rounded from .2475
1.00 L / b * .3 b = .30 L
1.01 L / b * .05 b = .05 L
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3.98 L / 4 b * 1.0 b = .99 L
Actual measurements might be 40 bottles at .98 L/b, 25 bottles at .99 etc
Then the total liters would be divided by the total number of bottles