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Reef Chemistry Question of the Day #103
One water change that replaces 30% of the aquarium's water obviously removes 30% of a pollutant in that water (assuming that none is in the new water and no special reservoir such as bound to rock or sand) and leaves 70% behind. If, instead, a series of 30 water changes, each replacing 1% of the total water, are performed, how much of the original pollutant will remain?
A. 99%
B. 90%
C. 74%
D. 50%
One water change that replaces 30% of the aquarium's water obviously removes 30% of a pollutant in that water (assuming that none is in the new water and no special reservoir such as bound to rock or sand) and leaves 70% behind. If, instead, a series of 30 water changes, each replacing 1% of the total water, are performed, how much of the original pollutant will remain?
A. 99%
B. 90%
C. 74%
D. 50%