This question is incomplete.
Complete Question
Astrid is in charge of building a new fleet of ships. Each ship requires 40 tons of wood, and accommodates 300 sailors. She receives a delivery of 4 tons of wood each day. The deliveries can continue for 100 days at most, afterwards the weather is too bad to allow them. Overall, she wants to build enough ships to accommodate at least 2100 sailors. How much wood does Astrid need to accommodate 2100 sailors?
Answer:
280 tons of wood.
Step-by-step explanation:
From the above question:
To make 1 ship = we require 40 tons of wood.
1 ship = can accommodate 300 sailors.
Step 1
If :
300 sailors = 1 ship
2100 sailors = y ships
Cross Multiply
300 × y ships = 1 ship × 2100 sailors
y ships = 2100 / 300
y ships = 7
Hence, 2100 sailors can occupy 7 ships.
Step 2
We are told in the question that:
Astrid wants to build enough ships to accommodate at least 2100 sailors. How much wood does Astrid need to accommodate 2100 sailors?
If:
1 ship = 40 tons of wood
Since 7 ships can accommodate 2100 sailors, 
7 ships =
7 × 40 tons of wood = 280 tons of wood.
Therefore , Astrid needs 280 tons of wood to accommodate 2100 sailors.
 
        
             
        
        
        
Answer:  Yes, y does vary directly with x.
Constant of variation = 1/4
The function rule is  y = (1/4)x
=========================================================
Explanation:
Let's assume that y does vary directly with x.
If that's the case, then we have an equation in the form y = kx, where k is the constant of variation.
Solving for k gets us k = y/x
For each row, divide the y value over the x value
- row one: k = y/x = 14/56 = 0.25
 - row two:  k = y/x = 20/80 = 0.25
 - row three: k = y/x = 22/88 = 0.25
 
Each row yields the value k = 0.25 and it fully confirms y does vary directly with x.
So y = kx becomes y = 0.25x as the function rule, which is equivalent to y = (1/4)x
 
        
             
        
        
        
Answer:
The volume of the concentrated 80 gallons mixture is 20 gallons
The volume of water in the 80 gallons mixture is 60 gallons
Step-by-step explanation:
The given parameters are;
The content of Container A = The cleaner
The concentration of the cleaner = 20% solution
The content of Container B = Pure water
The concentration of the desired solution = 5%
The volume of the required solution = 80 gallons
Let x represent the volume of the concentrated solution and y represent the volume of water in the 80 gallons mixture
Therefore, we have;
20/100 × x + y×0 = 5/100×80
x + y = 80
y = 80 - x
20/100 × x + (80 - x)×0 = 5/100×80
0.2·x = 4
x = 4/0.2 = 20
x = 20 gallons
 y = 80 - x = 80 - 20 = 60
y = 60 gallons
The volume of the concentrated solution (80 gallons mixture) = x = 20 gallons
The volume of water in the 80 gallons mixture = y = 60 gallons.
 
        
             
        
        
        
Answer:
47 cm²
Step-by-step explanation:
3(9 - 4) + 8 × 4 = 15 + 32 = 47