Question

a chemical company makes two brands of antifreeze. the first brand is 45% pure antifreeze and the second brand is 70% pure antifreeze. in order to obtain 170 gallon of a mixture that contains 65% pure antifreeze how many gallons of each brand of antifreeze mudt be used

Answer 1

The first brand is 34 gallons

The second brand is 136 gallons

Step-by-step explanation:

Let x represent the first brand, and

y represent the second brand

The total number of gallons of mixture to be obtained is 170, so

x + y = 170 .................................................................................(1)

And

45% of x + 70% of y = 65% of (x + y)

0.45x + 0.7y = 0.65(x + y)

0.45x - 0.65x = 0.65y - 0.7y

0.2x = 0.05y

Divide both sides by 0.05

4x = y ...........................................................................................(2)

Solving (1) and (2) simultaneously

Using (2) in (1)

x + 4x = 170

5x = 170

Divide both sides by 5

x = 170/5 = 34

Put x = 34 in (2)

4(34) = y

y = 136