A statistician creates a website to analyze sports statistics. His goal is to gain 70,000 followers in the next eight years so that he can sell his site to a news outlet. His prelaunch efforts result in 500 users signing up at the launch of the site. If his yearly growth rate is 0.778, then how many followers will he have after eight years? Round the answer to the nearest whole number.(1 point)

1 answer

To calculate the number of followers after eight years given the initial number of users and the yearly growth rate, we can use the formula for exponential growth:

\[ N = N_0 \cdot (1 + r)^t \]

Where:

  • \( N \) is the number of followers at time \( t \).
  • \( N_0 \) is the initial number of followers (500).
  • \( r \) is the growth rate (0.778).
  • \( t \) is the time in years (8).

Substituting the values into the formula:

\[ N = 500 \cdot (1 + 0.778)^8 \]

Calculating \( (1 + 0.778) \):

\[ 1 + 0.778 = 1.778 \]

Now raise it to the power of 8:

\[ 1.778^8 \approx 118.8393 \]

Now multiply by the initial number of followers:

\[ N \approx 500 \cdot 118.8393 \approx 59419.65 \]

Rounding to the nearest whole number, the expected number of followers after eight years is:

\[ N \approx 59420 \]

Thus, the statistician will have approximately 59,420 followers after eight years.