This is the 7279th most frequent Russian word.
вперемешку
Mixed together; in a jumble.
Here, 'вперемешку' is used to describe the mixing of different types of food (vegetables and fruits) together into a single dish, indicating variety and incorporation.
В салате были овощи вперемешку с фруктами.
In the salad, there were vegetables mixed with fruits.
'Вперемешку' here characterizes the lack of organizational structure among the books on the shelf.
Книги на полке стояли вперемешку, без какого-либо порядка.
The books on the shelf were arranged in a mixed way, without any order.
In this instance, 'вперемешку' implies that the toys are not sorted or separated, but instead intermingled among the children as they play.