Answer:
3 years
Step-by-step explanation:
Let y = number of orangutans, and let x = number of years.
For each study, the population, y, after x years is:
First study:
y = 784 - 25x
Second study:
y = 817 - 36x
We set the populations equal and solve for x, the number of years.
784 - 25x = 817 - 36x
Add 36x to both sides. Subtract 784 from both sides.
11x = 33
Divide both sides by 11.
x = 3
Answer: 3 years