Answer:
The age of the person who entered the room is 15
Step-by-step explanation:
We are given:
Ages of 5 people in a room are:
17, 16, 15, 17, 22
A person enters room, and then the mean age of 6 people is 17.
We need to find the age of person who entered the room.
The formula to calculate mean is: 
Now, in question we are given mean of 6 people that is 17
The age of 5 people are given while age of one person who enters the room is unknown.
Let age of person whose age is unknown= x
Now finding x using mean formula

So, The value of x: x=15
Hence, the age of the person who entered the room is 15
Answer:

Step-by-step explanation:
We must develop three equations in three unknowns.
I will use these three:



Answer: A- $5,250
B- $7,750
<em>Answer:</em>
<em>The value of the number should be 1 (or less I think)</em>
<em>Step-by-step explanation:</em>
<em>At most means the highest value of the sum should be 27.</em>
<em>10x + 17 = 27</em>
<em>10x = 27 - 17</em>
<em>10x = 10</em>
<em>x = 10/10</em>
<em>x = 1</em>
<em>∴</em><em>The value of the number should be 1</em>