This question is incomplete, the complete question as well as the missing diagram is uploaded below;
Consider a mixing tank with a volume of 4 m³. Glycerin flows into a mixing tank through pipe A with an average velocity of 6 m/s, and oil flow into the tank through pipe B at 3 m/s. Determine the average density of the mixture that flows out through the pipe at C. Assume uniform mixing of the fluids occurs within the 4 m³ tank.
Take  = 880 kg/m³ and
 = 880 kg/m³ and  = 1260 kg/m³
 = 1260 kg/m³     
  
 
Answer:
the average density of the mixture that flows out through the pipe at C is 1167.8 kg/m³   
Explanation:
Given that;
Inlet velocity of Glycerin,  = 6 m/s
 = 6 m/s
Inlet velocity of oil,  = 3 m/s
 = 3 m/s  
Density velocity of glycerin,  = 1260 kg/m³
 = 1260 kg/m³
Density velocity of glycerin, Take  = 880 kg/m³
 = 880 kg/m³
Volume of tank V = 4 m
from the diagram;
Diameter of glycerin pipe,  = 100 mm = 0.1 m
 = 100 mm = 0.1 m
Diameter of oil pipe,  = 80 mm = 0.08 m
 = 80 mm = 0.08 m
Diameter of outlet pipe  = 120 mm = 0.12 m
 = 120 mm = 0.12 m
Now, Appling the discharge flow equation;


π/4 × ( )²
)² + π/4 × (
 + π/4 × ( )²
 )² = π/4 × (
 = π/4 × ( )²
)²
we substitute
π/4 × (0.1 )² × 6 + π/4 × (0.08 )² × 3 = π/4 × (0.12)² 
 
 0.04712 + 0.0150796 = 0.0113097 
 
 0.0621996 = 0.0113097 
 
 = 0.0621996 / 0.0113097
 = 0.0621996 / 0.0113097
 = 5.5 m/s
  = 5.5 m/s 
Now we apply the mass flow rate condition
 
 
 
  
so we substitute
1260 × π/4 × (0.1 )² × 6 + 880 × π/4 × (0.08 )² × 3 = p × π/4 × (0.12)² × 5.5
1260 × 0.04712 + 880 × 0.0150796 = p × 0.06220335
59.3712 + 13.27 = 0.06220335p  
72.6412 = 0.06220335p    
p = 72.6412 / 0.06220335
p =  1167.8 kg/m³   
Therefore, the average density of the mixture that flows out through the pipe at C is 1167.8 kg/m³