Question

The following are the ages (years) of 5 people in a room: 16, 25, 23, 12, 17 A person enters the room. The mean age of the 6 people is now 20. What is the age of the person who entered the room?

Answer 1

Answer: 27

Step-by-step explanation:

• Set the age of the person who entered the room as x

$Mean=\frac{16 + 25 + 23 + 12 + 17 + x}{6}=20 \\16 + 25 + 23 + 12 + 17 + x=20(6)\\93+x=120\\x=120-93=27$

Answer 2

Answer:

27 years old

Step-by-step explanation:

There are originally 5 people in the room.

Their ages are: 16, 25, 23, 12, 17

The sum of their ages is: 93

One person enters the room. That person's age is unknown, so we call it x.

The sum of the ages of the 6 people is:

x + 93

There are 6 people in the room now, so the mean age is (total age divided by number of people):

(x + 93)/6

We are told the mean age is 20.

(x + 93)/6 = 20

x + 93 = 120

x = 27

Answer: 27 years old