First, combine the solution and salt: 120 liters + 80 liters = 200 liters. The percentages average out: 5% + 15% = 20%. Therefore, the ratio is 20:200, leading to a concentration calculation of 20/200 = 0.10. Ultimately, the final concentration is 10% salt.
Response:
The goat population will reach 1000 in a time span of 12.4 years
Detailed explanation:
After t years, the population of goats is described by

where
indicates the initial count of goats and b is the growth rate per capita.
Based on the problem,
- b = 0.5
- N = 1000




Let the number be x. The equation x/5 - 17 = 48 leads to (x - 85)/5 = 48. Multiplying gives x - 85 = 240, so x = 240 + 85, resulting in x = 325.