Answer:
Therefore the concentration of salt in the incoming brine is 1.73 g/L.
Step-by-step explanation:
Here the amount of incoming and outgoing of water are equal. Then the amount of water in the tank remain same = 10 liters.
Let the concentration of salt  be a gram/L
Let the amount salt in the tank at any time t be Q(t).

Incoming rate = (a g/L)×(1 L/min)
                        =a g/min
The concentration of salt in the tank at any time t is =  g/L
  g/L
Outgoing rate =  
 


Integrating both sides

 [ where c arbitrary constant]
        [ where c arbitrary constant]
Initial condition when t= 20 , Q(t)= 15 gram


Therefore ,
 .......(1)
 .......(1)
In the starting time t=0 and Q(t)=0 
Putting t=0 and Q(t)=0  in equation (1) we get









Therefore the concentration of salt in the incoming brine is 1.73 g/L
 
        
             
        
        
        
It is sometimes called an extreme value. When you graph an outlier, it will appear not to fit the pattern of the graph. Some outliers are due to mistakes (for example, writing down 50 instead of 500) while others may indicate that something unusual is happening
        
             
        
        
        
Answer:
each hamburger costs $3.50
Step-by-step explanation:
he spent $13 in total and bought one hot dog for $2.50 and 3 hamburgers but we don't know the price of one hamburger so we could represent it by the equaton,
2.50 + 3h = 13 now solve for x 
-2.50           2.50
3h = 10.50 
h=3.50 
check:
2.50+3(3.50)=13
2.50+10.50=13
13=13
 
        
             
        
        
        
Answer: $22.50
Step-by-step explanation:
25% of 30 = 7.5
30 - 7.5 = 22.50