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How many gallons of a 10% acid solution must be mixed with 5 gal of a 30% acid solution to make a 14% acid solution?
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Let "x" be a required amount of the 10% acid solution, in gallons.
Then the 10% solution contains 0.1*x gallons of the pure acid.
The 5 gallons of 30% acid solution contains 0.3*5 gallons of the pure acid.
After mixing, the new solution contains 0.1x + 0.3*5 of the pure acid, while the total volume of the solution is (5+x) gallons.
The equation for concentration of the new solution is
= 0.14.
To solve it, multiply both sides by (5+x). You will get
0.1x + 1.5 = 0.14*(5+x), or
0.1x + 1.5 = 0.7 + 0.14x, or
1.5 - 0.7 = 0.14x - 0.1x, or
0.8 = 0.04x.
Hence, x = = 20 gallons.
Answer. 20 gallons of the 10% acid solution must be added.
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- Mixture problems
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- Solving typical word problems on mixtures for solutions
- Word problems on mixtures for antifreeze solutions
- Word problems on mixtures for dry substances like coffee beans, nuts, cashew and peanuts
- Word problems on mixtures for dry substances like candies, dried fruits
- Word problems on mixtures for dry substances like soil and sand
- Word problems on mixtures for alloys
- Typical word problems on mixtures from the archive
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