The following are the ages (years) of 5 people in a room: 20, 24, 13, 15, 25 a person enters the room. the mean age of the 6 people is now 19. what is the age of the person who entered the room?

Prove that quadrilateral is a rhombus.

If 2(a^2+b^2)=(a+b)^2 then, > a+b=0, > ab=0, > a=b, > 2a=b

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.