Since the beginning of $2000$, the number of rabbits in a certain wooded area has tripled during every $4$-year period of time. If there were $6,210$ rabbits in the wooded area at the beginning of $2012$, how many rabbits were in the wooded area at the beginning of $2000$

เฉลยละเอียด

[STEP]Calculate how many times the number of rabbits triple[/STEP]

From $2000$ to $2012$, the number of rabbits triple $\frac{2012-2000}{4}=3$ times.

[STEP]Calculate the number of rabbits at the beginning of $2000$[/STEP]

Suppose there were $n$ rabbits at the beginning of $2000$. At the beginning of $2012$ the number of rabbits would be 

\begin{eqnarray*}
n\times3^{3} & = & 6210\\
n & = & \frac{6210}{3^{3}}\\
& = & 230
\end{eqnarray*}

[ANS]$230$[/ANS]

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