3a -- two coupled C# classes

3a.cs

public class Adder {
	public int AddTwoRandomNumbers() {
		var generator = new RandomNumberGenerator();
		var firstInt = generator.Generate();
		var secondInt = generator.Generate();
		return firstInt + secondInt;
	}
}

public class RandomNumberGenerator {
	public int Generate() {
		Random rnd = new Random();
		return rnd.Next();
	}
}