translate the given information into a system of equations the question is below.

Question

this the qouestion

1.Brand A and brand b rubbing alcohol contain 50% and 70% ethyl alcohol,respectively.how much of the 2 brands need tobe mixed in order to produce a 16liter mixture contains 62.5% ethyl alcohol?

 

Answer 1

Let A = the number of Liters of the 50% solution.  50% = .5

Let B = the number of Liters of the 70% solution. 70% = .7

 

We know that the total volume at the end is 16L.  So, A + B = 16, therefore, A = 16 - B

 

We also know that .5A + .7B = 16(.625)

Solve and substitute: .5(16 - B) + .7B = 10 ( 10 = 6(.625))

So,                            8 - .5B + .7B = 10

                                 .2B = 2

                                  B = 10

Therefore, because A + B = 16, A = 6