Step-by-step explanation:
✧ 
Let the age of a person who entered the room be ' x '.
✧ 
- 14 , 14 , 18 , 18 , 22 , x
n ( number of observation ) = 6
x = 14 + 14 + 18 + 18 + 22 + x = 86 + x
Mean = 16
☯ 
~Plug the values :
⇢ 
~Apply cross product property :
⇢ 
⇢ 
Move 86 to right hand side and change it's sign
⇢ 
⇢ 

Hope I helped ! ツ
Have a wonderful day / night ! ♪
⋆ Let me know if you have any questions regarding my answer ⋆
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