Why does it make sense to describe an equation that has infinitely many solutions as an identity?

What is this inequality notation? t is less then or equal to 2

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

According to the data set, where should the upper quartile line of the box plot be placed?