155+137+25=317°
360° -317°= 43°
Given:
The mean age of 5 people in a room is 26 years.
A person enters the room. The mean age is now 33.
To find:
The age of the person who entered the room.
Solution:
Formula for mean:

The mean age of 5 people in a room is 26 years.



The mean age is now 33. It means, the mean age of 6 people is 33.



Now, the age of the person who entered the room is
Required age = Sum of ages of 6 people - Sum of ages of 5 people
= 
= 
Therefore, the age of the person who entered the room is 68 years.
It would take her 10 hours. If it is double the time for one person to complete the task versus two, you can guess that the other person takes the same amount of time
Answer:
1/9
Step-by-step explanation:
3^-2
Remember that the negative exponent moves it to the denominator
1
---------
3^2
1
-----
9