Why does this happen in Java? With two equal numbers

// Reason 16 decimals ->> Output: 11 double num1 = 10.9999999999999999; Integer res1 = (int) Math.floor(num1); System.out.println(res1); // Reason 15 decimals ->> Output: 10 double num2 = 10.999999999999999; Integer res2 = (int) Math.floor(num2); System.out.println(res2); // Can you get 10 in both cases?