A fuel is purified by passing it through a clay pipe. Each foot of the clay pipe removes a fixed percentage of impurities in the fuel. Let f (x) represent the amount of pollutants, in tons, left in the fuel after it had passed through x feet of the clay pipe.

f (x) = 10 (0.8) x

What does the number 0.8 represent?

Every foot of the pipe removes 20% of the pollutant.

Every foot of the pipe removes 80% of the pollutant.

The original amount of pollutant present in the fuel was 80 tons.

The original amount of pollutant present in the fuel was 20 tons.

Question

Chemistry

Tapia

22 November, 07:19

A fuel is purified by passing it through a clay pipe. Each foot of the clay pipe removes a fixed percentage of impurities in the fuel. Let f (x) represent the amount of pollutants, in tons, left in the fuel after it had passed through x feet of the clay pipe.

f (x) = 10 (0.8) x

What does the number 0.8 represent?

Every foot of the pipe removes 20% of the pollutant.

Every foot of the pipe removes 80% of the pollutant.

The original amount of pollutant present in the fuel was 80 tons.

The original amount of pollutant present in the fuel was 20 tons.

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Answers (1)

Know the Answer?

Chanel Cruz · Answer 1

Answer: first option, Every foot of pipe removes 20% of the pollulant.

Explanation:

20% removal means that after passing every foot of clay pipe, 80% of pollulant remains = 80/100 = 0.8

Then the amount of pollulant left in the fuel after passing x feet will be A*0.8^x

f (x) = 10 (0.8) ^x

Initial amount, A = > x = 0 = > f (0) = 10 = A

After one foot: 10 - 0.2 (10) = 10*0.8

After two feet: 10*0.8 - 10*0.8*0.2 = 10*0.8[1-0.2] = 10*0.8*0.8 = 10*0.8^2

After three feet: 10*0.8^3

After n passes: 10*0.8^n