Answer:
Cleanser that costs 50 cents is 1400 liters, Cleanser that costs 80 cents is 600 liters.
Step-by-step explanation:
We can solve this by using <em>simultaneous equations</em>:
- Let us express the question in terms of equations
Let a be cleanser at 50 cents and let b be the cleanser at 80 cents.
Equation 1: 0.5a + 0.8b = 0.59(a+b)
Equation 2: a + b = 2000
From equation 2, a = 2000 - b (Let's call this equation 3)
2. Substituting equations 2 and 3 in Equation 1:
0.5a + 0.8b = 0.59(a+b)
0.5(2000 - b) + 0.8b = 0.59(2000)
1000 - 0.5b + 0.8b = 1180
0.3b = 180
b = 600
Substitute in equation 3:
a = 2000 - 600
a = 1400
As a note, I formed equation 1 because I know for a fact the cost per liter of a and b. I also know it is sold at 0.59 cents per liter. We are selling 2000 liters in this instance, therefore 0.59(2000) = 1180, which in this case is the selling price.
and differentiating both sides with respect to 
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