Final answer:
To find the total number of books on Oksana's bookcase, you divide the number of books she has read by 2/7 to get 1/7 of the total, which equals 14 books, and then multiply by 7 to get the entire bookcase, resulting in 98 books.
Step-by-step explanation:
Oksana has read 2/7 of the books on her bookcase and the number of books she has read is 28. To find the total number of books on her bookcase, we can set up an equation and solve for the total number. Since 2/7 represents 28 books, we can divide 28 by 2 to find out what 1/7 of the bookcase contains, then multiply by 7 to find the total number of books.
- First, find the value of 1/7: 28 ÷ 2 = 14 books.
- Then, multiply this value by 7 to get the total: 14 × 7 = 98 books.
Therefore, the total number of books on Oksana's bookcase is 98.