Two years ago, there were 30 foxes in a forest. this year, there are 40 foxes in the forest. what is the annual percent growth for the foxes?

9514 1404 393

  about 15.5%

Step-by-step explanation:

The number of foxes in the forest can be modeled by the exponential equation ...

  f = a·b^t

where a is the initial number, and b is the growth factor per year for t years. The growth factor is 1 more than the growth rate (r), so we can put numbers in this formula to get ...

  40 = 30·(1 +r)^2

  4/3 = (1 +r)^2 . . . . . . divide by 30

  1 +r = √(4/3) . . . . . .  take the square root

  r = √(4/3) -1 ≈ 0.1547 ≈ 15.5%

The annual percentage growth in the fox population is about 15.5%.

b. x- 48 =120

step-by-step explanation: