Algebra Demystified 2nd Ed

Chapter 8 linear appliCaTionS 267

PRACTICE

1. How much 60% acid solution should be added to 8 liters of 25% acid
   solution to produce a 40% acid solution?


2. How many quarts of^12 % fat milk should be added to 4 quarts of 2% fat
   milk to produce 1% fat milk?


3. How much 30% alcohol solution should be mixed with 70% alcohol
   solution to produce 12 liters of 60% alcohol solution?


4. How much 65% acid solution and 25% acid solution should be mixed
   together to produce 180 ml of 40% acid solution?


5. How much water should be added to 10 liters of 45% alcohol solution
   to produce a 30% solution?


6. How much decaffeinated coffee (assume this means 0% caffeine) and
   50% caffeine coffee should be mixed to produce 25 cups of 40% caf-
   feine coffee?


7. How much pure acid should be added to 18 ounces of 35% acid solution
   to produce 50% acid solution?


8. How many peanuts should be mixed with a nut mixture that is 40%
   peanuts to produce 36 ounces of a 60% peanut mixture?

✔SOLUTIONS

1. 60% 25% 40%
   x
   liters

+^8

liters

= x + 28

liters

0.60x + 0.25(8) = 0.40(x + 28)

0600258040 8

060204032

040

..() .( )

...

.

xx

xx

x

+=+

+= +

−− 0040

0202032

20 20

02012

12

020

.

...

..

..

.

.

x

x

x

x

x

+=

−−

=

=

= 66

Add 6 liters of 60% solution to 8 liters of 25% solution to produce a 40%

solution.

PRACTICE

1. How much 60% acid solution should be added to 8 liters of 25% acid