The mean age of 5 people in a room is 25 years.
A person enters the room.
The mean age is now 27.
What is the age of the person who entered the room?

Apublic library wants to place 4 magazines and 9 books on each display shelf. the expressions 4s +9s represents the total number of items that will be displayed on s shelves. simplify this expression

Abox contains 1 plain pencil and 4 pens. a second box contains 5 color pencils and 5 crayons. one item from each box is chosen at random. what is the probability that a plain pencil from the first box and a color pencil from the second box are selected? write your answer as a fraction in simplest form.

Identify the graph of y = ln x + 1.