Problema Solution

Polluted water is passed through a series of filters. Each filter removes 55% of the remaining impurities from the water. If you have 10 million particles of pollutant per gallon originally, how much pollution will you have after 4 passes through the filters?

Answer provided by our tutors

10 million particles = 10^6 particles


since the water passes through 4 filters we have:


0.55*0.55*0.55*0.55*10^6 = (0.55)^4 * 10^6 = 91,506 particles


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after 4 passes through the filters there will be 91,506 particles of pollutant per gallon.