Riddle me this Batman.....

WIMUSKY

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Math question. Math is hard. Lol
My wife and I are at a crossroad, we need you guys to break the tie.
I filled the motorhome with a 50/50(50%) mix of antifreeze/water. Took it for a drive and I need to add more, not sure how much since it has a sight glass.
I have 1/2gal of concentrate left that I want to use with no water mix. They say 60% antifreeze is the optimum mix for cold weather.
My question:
What will the antifreeze percentage be if I add the half gallon of concentrate???🤔

Thanx.....
 

flashback

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I ain't no math wiz but the volume of 50/50 you put in and engine capacity would be good to know.. LOL
 

WIMUSKY

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Sorry! 🤣
I put in 7gals of mix. Assume the 1/2gal will fill it. Not necessarily shooting for 60%.... Just want to see where I'm at....
 

racerone

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I had a couple of beers today !----A celebration of sorts.-----When I was in high school they taught me algebra.----They said " you have to know this stuff ".-----So today was day 18,143 since high school and I have never used algebra !!
 

WIMUSKY

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You would have put in 4 gallons of concentrate and 3-1/2 of water.----Total is 7.5 gallons.----Me thinks it is 53.333333 % mixture now.
That's exactly what I did...... Me thinks I over thought it....
I took all the higher math right thru HS many moons ago. Except my senior year, Trig. Sine, cosine and tangent, what the heck??? We had 3 days to dump the class, I took a study hall.... A mind is a terrible thing to waste... 🤣
Ps. Wife was right, dont tell her....😁 Somehow I came up with 57....

Thanks racer......
 

WIMUSKY

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If I'm a gallon low, which is possible (maybe), I can add straight concentrate and be at 56%... Just can't exceed 60%...
 
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Renken2000Classic

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I had to do that math a while back after changing some old transmission fluid. Ok, there's X left in the converter, so how many more times should I do that to get rid of a reasonable overall amount of the old? 1 maybe 2 more changes was the answer. Have yet do to even one of them though...
 

dwco5051

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I had to do that math a while back after changing some old transmission fluid. Ok, there's X left in the converter, so how many more times should I do that to get rid of a reasonable overall amount of the old? 1 maybe 2 more changes was the answer. Have yet do to even one of them though...
Once you decide what percentage of old to new is reasonable it would be a rather simple solution using differential calculus. Since it has been 63 years since I took that course I can't give you the how to off the top of my head. The last I and only time I ever solved a problem using it was making a capacity chart for sticking a 2000 gallon underground storage take some 40 years ago and I had to dig out my old college text book to solve it.
 

dwco5051

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Once you decide what percentage of old to new is reasonable it would be a rather simple solution using differential calculus. Since it has been 63 years since I took that course I can't give you the how to off the top of my head. The last I and only time I ever solved a problem using it was making a capacity chart for sticking a 2000 gallon underground storage take some 40 years ago and I had to dig out my old college text book to solve it.
Actually since the change in the ratio is linear it would be easy to use Excell to set up the formula. You would have to change the fluid an infinite number of times to achieve 100% new fluid. That is similar to moving an object to a wall by moving it one half the distance remaining at a time. They would never touch no matter how often you moved it.
 

WIMUSKY

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It turned out I was a little low. Dumped in a 1/2 gal of concentrate and calling it good..
 

roscoe

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Don’t worry. Gonna be a warm winter.

Not going below 25* this winter.

Probably won’t even need to turn on the furnace, so no need to buy the LP.
 
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