A spirit and water solution is sold in a market. The cost per liter of the solution is directly proportional to the part (fraction) of spirit (by volume) the solution has. A solution of 1 liter of spirit and 1 liter of water costs 80 cents. How many cents does a solution of 1 liter of spirit and 2 liters of water cost?  Choose the correct choice.
A) 53
B) 66
C) 60
D) 85
E) 80
Yes, ensure that you understand the relation thoroughly!   Cost per liter = K * Fraction of Spirit   80 cents is the cost of 2 liters of solution (1 part water, 1 part spirit). So cost per liter is 40 cents. Fraction of spirit is 1/2.   40 = K * (1/2)   K = 80   Cost per liter = 80 * (1/3) (1 part spirit, 2 parts water)   Cost for 3 liters = 80 * (1/3) * 3= 
<gadget id="calculator">80 * (1/3) * 3</gadget>
<output>80</output>
80 cents   E. 80 cents
<result>E</result>
A spirit and water solution is sold in a market. The cost per liter of the solution is directly proportional to the part (fraction) of spirit (by volume) the solution has. A solution of 1 liter of spirit and 1 liter of water costs 80 cents. How many cents does a solution of 1 liter of spirit and 2 liters of water cost?