.
Let W be the volume of water to dilute.
The amount of a pure acid is 0.2*25 ounces,
The total volume after dilution is (25 + W) ounces.
The equation for concentration is
= 0.1.
To solve, cross multiply
0.2*25 = 0.1*(25 + W).
Simplify
5 = 2.5 + 0.1W
W = = = 25.
ANSWER. 25 ounces of water.
Solved.
From the other side, the answer is OBVIOUS:
to dilute from 20% to 10%, Annabell must double the volume of the solution, i.e. add 25 ounces of water.
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There is entire bunch of lessons covering various types of mixture problems
- Mixture problems
- More Mixture problems
- 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
- Advanced mixture problems
- Advanced mixture problem for three alloys
- Unusual word problem on mixtures
- Check if you know the basics of mixtures from Science
- OVERVIEW of lessons on word problems for mixtures
in this site.
A convenient place to quickly observe these lessons from a "bird flight height" (a top view) is the last lesson in the list.
Read them and become an expert in solution the mixture word problems.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Mixture problems".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.