.
Please help me to solve this problem.
A certain paint mixture weighing 305 kg contains 22% solids suspended in water. How many kilograms of water must be allowed
to evaporate to raise the concentration of solids to 27%?
Treat the percents given in this exercise as exact numbers, and work to three significant digits.
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Let "w" be the mass of water evaporated.
Then the concentration equation is
= 0.27, or
0.22*305 = 0.27*(305-w).
Simplify and solve for "w":
67.1 = 82.35 - 0.27w, or
0.27w = 82.35 - 67.1 ---> 0.27w = 15.25 ---> w = = 56.48.
Answer. 56.481 kg of water must evaporate.
Quantity of water to evaporate = 56.481 kg.
Check. = 0.27. Correct!
There is entire bunch of the 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 alloys
- Typical word problems on mixtures from the archive
in this site.
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 textbook in the section "Word problems" under the topic "Mixture problems".
The textbook contains many other solved word problems, as well as many other interesting and useful things.