Mohammed is a financial analyst at GreenTech Manufacturing. He is reviewing the company's Statement of Financial Position to prepare for an upcoming audit. One of his tasks is to calculate the book value of the company's fixed assets, which include a factory building and machinery. The factory building was purchased for R$500000$ and the machinery for R$200000.$ Over the years, the accumulated depreciation on the building is R$100000$ and on the machinery is R$50000.$ Mohammed needs to determine the current book value of these fixed assets to ensure accurate financial reporting.

Which of the following statements best describes the concept of yield to maturity $($YTM$)?$