sophia finished 23 of a book . she calculated that she finished 90 more pages than she has yet to read . how long is her book ?
"let x be the total number of pages in the book , then she finished 23 ⋅ x pages . then she has x − 23 ⋅ x = 13 ⋅ x pages left . 23 ⋅ x − 13 ⋅ x = 90 13 ⋅ x = 90 x = 270 . so answer is d ."
divide(90, subtract(divide(const_2, const_3), subtract(const_1, divide(const_2, const_3))))