1. The problem states that the solution for $x$ is given as $0.615$ according to the marking guide. 2. To verify or understand this solution, we would need the original equation or context where $x$ is solved. 3. Since no equation or problem is provided, we accept the given answer $x = 0.615$ as the final solution. 4. If you provide the original problem or equation, I can help show the detailed steps to reach this answer.