Final answer:
To find the total number of pages in the book, use the equation 150 = 0.25x because Hark has read 25 percent of the book, which is equivalent to 150 pages. Solving for x, we find that the total number of pages is 600.
Step-by-step explanation:
The question is about finding the total number of pages in a book based on the percentage that has already been read. Since Hark has read 25 percent of the book, the total number of pages of the book is represented by 'x'. Knowing that 25 percent of the total is equivalent to 150 pages, we can set up the equation 150 = 0.25x to find 'x', the total number of pages in the book. To solve for 'x', divide both sides of the equation by 0.25, yielding x = 600. This tells us that the total number of pages in the book is 600.
It is important to note that the equation 150 = 0.25x correctly represents the relationship between what has been read and total pages, as 0.25 (or 25 percent) of the total number of pages is known to be 150 pages. Therefore, based on the options provided, answer c. 150 = 0.25x is the correct equation to use.