solutuon contains 2 parts salt to 8 parts water, another contains 3 parts salt to 5 parts water. How much of each should be mixed together to obtain 280 quarts of a solution that is 3 parts salt to 7 parts water?
Please help!!!

Question

solutuon contains 2 parts salt to 8 parts water, another contains 3 parts salt to 5 parts water. How much of each should be mixed together to obtain 280 quarts of a solution that is 3 parts salt to 7 parts water? 
Please help!!!

anonymous · Answer

The answer is 120 quartz of the 1st solution and 160 quarts of  the 2nd solution - I just don't understand how to work around this problem to get to the answer?

retireed · Answer

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anonymous · Answer

Thank you so much for trying....the answer that I mentioned is the actual answer but I too am thinking how to arrive at that answer.

retireed · Answer

This is what I think.  Does this look reasonable.
Try solving this equation for x....

I will too and see who gets there first :)

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anonymous · Answer

sure I will  do that and see what I get -thanks!

retireed · Answer

No that didn't work out.  I got x to be like 662 qt.  I looked so good, sorry.

anonymous · Answer

There seems to be some error there as the variable ts negative...did you see that?

anonymous · Answer

That is okay - at least you are trying to the best of your ability

retireed · Answer

Yes and negative,  I am missing something simple, but I can't find it.

retireed · Answer

I need to get some paper and a pen in order to work faster.

anonymous · Answer

lets say we want to mix the solutions in m:n ratio...

=> $$(2m+3n)/(8m+5n)$$ = 3/7

will that be correct ?

anonymous · Answer

let me see? thank you for trying

anonymous · Answer

but this leads to 105 and 175 as answers

anonymous · Answer

unfortunately its not as I have the answers already with me.....I'm sorry but it probably has to be done some other way.

retireed · Answer

I'm back on, but still stuck.  I know I have watched other helpers solve these in the past and I thought I could help, but I am going to have to search Google for help.

anonymous · Answer

no problem.......we can only try and thanks at least for trying. In case I get to the answer I will let you know

retireed · Answer

I found something that is very straight forward, but I still didn't get your answer.  

I hate to ask this, but could you check the question again and make sure the fractions (all three) are typed correct?

The answers I got were very close to my estimate,  137.15 and 142.85.

While you check I will type up my solution and let see if you can find my mistake.

anonymous · Answer

yes I did check and the question is correct. Someone had actually come in and gave the correct answer and left but did not explain how he/she got to that answer. In fact I too have the answer key with me which states the answers I quoted above

retireed · Answer

Here it is.  I give up, sorry.  

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