SOLUTION: a chemist needs to mix 20L of a 40% acid solution with some 70% acid solution to obtain a mixture that is 50% acid. How many liters of the 70% acid solution should be used?

Algebra.Com
Question 347300: a chemist needs to mix 20L of a 40% acid solution with some 70% acid solution to obtain a mixture that is 50% acid. How many liters of the 70% acid solution should be used?
Answer by checkley77(12844)   (Show Source): You can put this solution on YOUR website!
.70x+.40*20=.50(20+x)
.70x+8=10+.50x
.70x-.50x=10-8
.20x=2
x=2/.2
x=10 L of 70% acid is used.
Proof:
.70*10+.40*.2=.50(20=10)
7+8=.5*30
15=15

RELATED QUESTIONS

A chemist must mix 8 liters of 40% acid solution with some 70% solution to obtain a 50%... (answered by checkley77)
A chemist needs to mix a 20% acid soultion with 9 liters of a 47% acid solution to obtain (answered by richwmiller)
having problems with a mixture problem, could someone help me. the problem is a chemist... (answered by scott8148)
A chemist needs to combine two solutions of a certain acid. How many liters of a 30%... (answered by ptaylor)
A chemist needs to mix an 18% acid solution with a 45% acid solution to obtain a 12... (answered by josgarithmetic)
A chemist wants to create a solution that is 24% acid. How many liters of a 40% acid... (answered by josgarithmetic)
A chemist wants to create a solution that is 24% acid. How many liters of a 40% acid... (answered by richwmiller)
A chemist needs to mix a 10% acid solution with a 60% acid solution to obtain 50... (answered by jorel1380)
A chemist needs to mix a 75% acid solution with a 50% acid solution to obtain 10... (answered by KMST)