Question

The population of lemmings on an island in Norway varies drastically. In a base year, the population was n lemmings. The next year, it tripled. The third year, the number dropped by 3000 from the second year. The fourth year, the population was 1 2 that of the third year. The fifth year, it increased by 1300 to a total of 1450 lemmings. What is the value of n?

Answer 1

The initial population of lemmings on the island was 200.

Step-by-step explanation:

In the base year, the population of lemmings on the island was n. In the next year, the population tripled, so it became 3n.

In the third year, the number dropped by 3000 from the second year, so it became 3n - 3000.

In the fourth year, the population was half that of the third year, so it became (3n - 3000)/2. In the fifth year, it increased by 1300 to a total of 1450 lemmings, so we have the equation (3n - 3000)/2 + 1300 = 1450.

Solving this equation, we find that n = 200.