Question

The following are the ages (years) of 5 people in a room: 18, 21, 12, 12, 23 A person enters the room. The mean age of the 6 people is now 22. What is the age of the person who entered the room?

Answer 1

Answer:

46

Step-by-step explanation:

let the five people be : A , B , C , D and E

A's age = 18 ;  B's age = 21 ; C's age = 12 ; D's age = 12 and E 's age = 23

a sixth(F) person entered the room and the mean of their ages is now 22

Let us say the age of F is x because we do not know it

Average = $\frac{sum of items}{no. of items}$  = $\frac{18+21+12+12+23+x}{6} = \frac{86+x}{6}$ = 22

cross multiply

22 × 6 = 86 + x

132 = 86+ x

x= 132-86

x=46

∴age of F = 46

Answer 2

The following are the ages (years) of 5 people in a room: 18, 21, 12, 12, 23 A person enters the room. The mean age of the 6 people is now 22. What is the age of the person who entered the room.

Let the age of the person who entered the room be x.

The average year of 6 peoples =22

The sum of year of 6 peoples =22×6=132

a.q

=> 18+21+12+12+23+x = 132

=> 86+x = 132

=> x = 132-86

=> x =46

Hence, the age of the person who entered the room is 46 years.