Answer :
Answer:
g is a GEOMETRIC SEQUENCE
Explicit formula g(n) = [tex]900(\frac{1}{3})^{n-1}[/tex]
Step-by-step explanation:
If wanahton purified a portion of water with 900 grams of contaminants and each hour, a third of the contaminants was filtered out then the amount of grams filtered out first hour will be 1/3 of 900grams = 300grams.
The amount filtered out in the second hour will be 1/3 of 300grams = 100grams.
Given the initial amount of contaminant = 900g
Contaminant after 1st hour = 300g
contaminant after 2nd hour = 100g and so on
It is seen that the amount of contaminant keep reducing by one third each hour. The sequence formed will be 900, 300, 100... which is a GEOMETRIC SEQUENCE because they are reducing by the same factor each term which is 1/3.
Given the geometric sequence 900, 300, 100...the nth term of the sequence is expressed as shown;
g(n) = [tex]ar^{n-1}[/tex]
r is the common ratio = [tex]\frac{300}{900}= \frac{100}{300}[/tex] = [tex]\frac{1}{3}[/tex]
n is the umber of terms
a is the first term which serves as the initial value of the contaminant= 900
Substituting the values given to get the explicit formula for the sequence we have;
g(n) = [tex]900(\frac{1}{3})^{n-1}[/tex]
The amount of contaminants (in grams) that remained by the beginning of the nth hour is [tex]900(\frac{1}{3})^{n-1}[/tex]