Question

A particular strain of bacterium has 20 bacteria in generation 1 and triples in population every generation. The explicit formula for the number of bacteria in generation n is:How many bacteria are in generation 9?

Answer 1

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SOLUTION

`\begin{gathered} Given\text{ that } \\ \text{a\lparen n\rparen=20}*3^((n-1)) \\ where\text{ n is generation} \end{gathered}`
`when\text{ n=9, a\lparen n\rparen=?}`
`\begin{gathered} a(9)=20*3^(9-1)=20*3^8 \\ a(9)=20*6561 \\ a(9)=131220 \end{gathered}`

The answer is 131220