graphics uses one cleanser that s 25% acid and a second that is 50% acid. how many liters of each should be mixed to get 30L of a solution that is 40% acid?
30 L of 40% cleanser will contain 30 * 40% = 12 L acid.
Let there be V1 L of cleanser at 25% giving V1 * 25% = V1/4 L of acid
Let there be V2 L of cleanser at 50% giving V2 * 50% = V2/2 L of acid
Therefore V1/4 + V2/2 = 12 --------- (1)
And V1 + V2 = 30 -------------------- (2)
Multiplying (1) by 4,
V1 + 2V2 = 48 -------------------------- (3)
V1 + V2 = 30 --------------------------- (2)
Subtracting (2) from (3),
V2 = 18. therefore, V1 = 30 - 18 = 12
Answer: Mix together 12 L of the 25% cleanser and 18 L of the 50% cleanser to get 30 L of 40% cleanser