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# The international Red Cross is making plans to ...

## Tags: Mathematik

04:28 Uhr, 26.06.2022

Tag!
The international Red Cross is making plans to airlift emergency food and medical supplies into a large city which has experienced an earthquake. Four items will be will be airlifted in containers to aid the recovery from the earthquake. The four items to be considered for the first airplane to be sent to the city as well as the volume are shown in the table below:

T
I tried to attach a screenshot of the rest of the exercise.

I know that I have to set up four equations to solve the problem but it is too difficult without your help

Thank you

Für alle, die mir helfen möchten (automatisch von OnlineMathe generiert):
"Ich möchte die Lösung in Zusammenarbeit mit anderen erstellen."

04:45 Uhr, 26.06.2022

Hi,

please attach the whole exercise. Haven't you seen that something is missing?

greetings,
pivot

15:03 Uhr, 26.06.2022

@pivot
Auch wenn der Text im Bild abgeschnitten ist steht doch alles Nötige da, um die vier Gleichungen aufzustellen.

@RASTA
How about to make a try and show the equation(s) you had set up so far?
In case you already solved th eproblem and only want to know if your results are correct:
The solution is (number of containers):
Blood:50; Medical Supply: $100;$ Food: $25$ and Water:300

15:29 Uhr, 26.06.2022

@roman-22
Die Aufgabe ist trotzdem nicht vollständig. Ob es sich um Ungleichungen (inequalities) oder Gleichungen (equalities) handelt ist nicht klar.

15:38 Uhr, 26.06.2022

well, this is what i have been given.

blood
volume=20ft^3
weight=150 lbs
cost= $1000$

medical supplies/kits
volume=30ft^3
weight=100 pds
cost=$300$

water
volume=6ft^3
weight= 70 pounds
cost $200$

volume capacity = 6,000 ft^3
weight capacity = 40,000 lbs
total budget= $150,000$

the number of containers of water should be twice the combined number of blood and medical supplies.

i know i must set up four equations but do not know how to begin. give me a hint support me till i get to the solution so i can learn how to do it.

vielen dank

16:22 Uhr, 26.06.2022

@pivot
$>$ Ob es sich um Ungleichungen (inequalities) oder Gleichungen (equalities) handelt ist nicht klar.
Für mich eigentlich schon. Der letzte (unvollständige) Satz fordert für mich klar die Gleichheit und frägt, ob es da eine mögliche Verteilung gibt mit der das erreicht werden kann. Es fehlt nur am Schluss der Teil, welcher Anforderung diese Aufteilung noch genügen soll und das wird wohl ziemlich sicher die Sache mit dem Wasser sein.

@RASTA
You are just repeating the given values which are already clear anyway.
I'd suggest you name the number of containers containing blood $B\phantom{\rule{0.12em}{0ex}},$ medical sypply $M\phantom{\rule{0.12em}{0ex}},$ Food $F\phantom{\rule{0.12em}{0ex}}$ and Water W.

The first requirement ist the given volume space of $6000{f\phantom{\rule{0.12em}{0ex}}t\phantom{\rule{0.12em}{0ex}}}^{3}$ in the airplane. This is supposed to be exactly the space that all the containers together also occupy (we assume that it is possible to stack all containers without any gaps).

Each blood container takes up $20{f\phantom{\rule{0.12em}{0ex}}t\phantom{\rule{0.12em}{0ex}}}^{3}$ and so the space needed for all $B\phantom{\rule{0.12em}{0ex}}$ blood containers is $B\phantom{\rule{0.12em}{0ex}}\cdot 20{f\phantom{\rule{0.12em}{0ex}}t\phantom{\rule{0.12em}{0ex}}}^{3}$. Analogously for the other three goods.
Therefore, neglecting the units, the first equation is

$20B\phantom{\rule{0.12em}{0ex}}+30M\phantom{\rule{0.12em}{0ex}}+8F\phantom{\rule{0.12em}{0ex}}+6W\phantom{\rule{0.12em}{0ex}}=6000$

And now you go on $..$.

16:24 Uhr, 26.06.2022

i am gonna try to set up equation #1

for blood

cost = volume + weight
1,000= 20ft^3 + 150 lbs

but i see the units are different . i have cubic ft and pounds

schwerig!

16:24 Uhr, 26.06.2022

i am gonna try to set up equation #1

for blood

cost = volume + weight
1,000= 20ft^3 + 150 lbs

but i see the units are different . i have cubic ft and pounds

schwerig!

16:28 Uhr, 26.06.2022

Your approach is unfortunately completely wrong, but the realisation that the units do not fit is very good and important. Volume and weight don't add up to currency ;-)
See my last answer what the first equation may look like.

17:36 Uhr, 26.06.2022

roman, just one question,
in the first equation you set up as a model for me, i see that everything is dealing with volume and each volume is given in cubic ft, why have you omitted the ft^3 ?

17:54 Uhr, 26.06.2022

Because its easier to deal with the unitless equations. Its perfectly OK to omit the units in this case as you may see at as "cancelling" the factor ${f\phantom{\rule{0.12em}{0ex}}t\phantom{\rule{0.12em}{0ex}}}^{3}$ in the whole equation (dividing both sides by ${f\phantom{\rule{0.12em}{0ex}}t\phantom{\rule{0.12em}{0ex}}}^{3}\right)$

$20B\phantom{\rule{0.12em}{0ex}}+30M\phantom{\rule{0.12em}{0ex}}+8F\phantom{\rule{0.12em}{0ex}}+6W\phantom{\rule{0.12em}{0ex}}=6000$

and it would have been better to divide both sides by 2 as well.

You can do so likewise with the weight-equation and the cost-equation.
The equation regarding the water containers being twice the number of the combined blood and med supply containers is unitless anyway.

21:19 Uhr, 26.06.2022

thanks a lot for the support

here's my two equations for the wight and for the cost, modeling the One you set up for the volume.

150B + 100M + 60F + 70W =40,000 lbs

1,000B + 300M + 400F + W200=150,000 dollars

the number of containers of waters that are going to be shipped should be twice the combined number of blood and medical supplies

I will give it a try

2W( B + M)

22:55 Uhr, 26.06.2022

Your two equations are correct, but if you divide by the units in the LHS, you also have to do it on the RHS $\to$ no pounds and no dollars anywhere.

$>2W\phantom{\rule{0.12em}{0ex}}\left(B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}\right)$
I can't see an equals sign there - so it's not an equation either!

If $B\phantom{\rule{0.12em}{0ex}}$ and $M\phantom{\rule{0.12em}{0ex}}$ together have a certain number of marbles and $W\phantom{\rule{0.12em}{0ex}}$ alone has twice as many - how would you 'cast' this into an equation?

23:32 Uhr, 26.06.2022

THANK YOU.

the number of container of waters should twice the combined number of blood and medical kits
I know that 'twice' = multiplication
and 'combine' is used for addition so,

2W = B + M

02:03 Uhr, 27.06.2022

$>I\phantom{\rule{0.12em}{0ex}}$ know that 'twice' = multiplication
Correct, but $..$.

If A has twice as much money as $B\phantom{\rule{0.12em}{0ex}}-$ who has more money?
And which equation is valid now: $2\cdot A\phantom{\rule{0.12em}{0ex}}=B\phantom{\rule{0.12em}{0ex}}$ or $2\cdot B\phantom{\rule{0.12em}{0ex}}=A\phantom{\rule{0.12em}{0ex}}$?
If you are unsure, just put in concrete numbers and check which equation is correct.

14:24 Uhr, 27.06.2022

if A has twice as much money as B then A has more money than B. in fact A doubles the amount that B has.

14:26 Uhr, 27.06.2022

So you now know what was wrong when you wrote $2W\phantom{\rule{0.12em}{0ex}}=B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}$

15:48 Uhr, 27.06.2022

So, 2&times;w(B+M)=150,000

17:32 Uhr, 27.06.2022

$>$ So, 2&times;w(B+M)=150,000
?????????????

18:24 Uhr, 27.06.2022

2w(B+M)= 1900

1900 is the total cost for all containers.

22:30 Uhr, 27.06.2022

$>1900$ is the total cost for all containers.
Why do you thinks so?
And why do you think that multiplying two quantities (number of W-containers and combined numbers of $B\phantom{\rule{0.12em}{0ex}}&M\phantom{\rule{0.12em}{0ex}}$ containers) gives you a quantity with unit Dollars?

Lets go back to my example with A and B. Lets call them $X\phantom{\rule{0.12em}{0ex}}$ and $Y\phantom{\rule{0.12em}{0ex}}$ now to avoid ambiguity because of the letter $B\phantom{\rule{0.12em}{0ex}}$
$X\phantom{\rule{0.12em}{0ex}}$ has twice as much money than Y. You answered correctly that this means that $X\phantom{\rule{0.12em}{0ex}}$ has more money than $Y\phantom{\rule{0.12em}{0ex}}$ but you did not answer the question after the correct equation. Is it $2\cdot X\phantom{\rule{0.12em}{0ex}}=Y\phantom{\rule{0.12em}{0ex}}$ or $X\phantom{\rule{0.12em}{0ex}}=2\cdot Y\phantom{\rule{0.12em}{0ex}}$?
A hint: Its sure not $2\cdot X\phantom{\rule{0.12em}{0ex}}\cdot Y\phantom{\rule{0.12em}{0ex}}=a\phantom{\rule{0.12em}{0ex}}n\phantom{\rule{0.12em}{0ex}}y\phantom{\rule{0.12em}{0ex}}n\phantom{\rule{0.12em}{0ex}}u\phantom{\rule{0.12em}{0ex}}m\phantom{\rule{0.12em}{0ex}}b\phantom{\rule{0.12em}{0ex}}e\phantom{\rule{0.12em}{0ex}}r\phantom{\rule{0.12em}{0ex}}$ as you suggested in your last reply ;-)
I suggested to put in numbers if you are unsure and see which equation is correct.
For example you may set $X\phantom{\rule{0.12em}{0ex}}=200$ $and $Y\phantom{\rule{0.12em}{0ex}}=100$$.

When you have decided on one of the two equation you can go on to your task.
"W should be twice the combined number of containers $B\phantom{\rule{0.12em}{0ex}}$ and M"
So in the example above you may set $X\phantom{\rule{0.12em}{0ex}}=W\phantom{\rule{0.12em}{0ex}}$ and $Y\phantom{\rule{0.12em}{0ex}}=\left(B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}\right)$.

Now you should have a correct fourth equation (and it sure does neither contain $150000$ nor $1900\right)$.

23:39 Uhr, 27.06.2022

the correct equation of the two you posted was
2 * A =B because A has twice as much money than B. That is clear
But I am still confused
as to how to set up this:
the number of containers of water should be twice the combine number of blood and medical suppplies

here it doesn't say twice as much. it is not twice as much. it is that, there should be twice the amount of water than that of blood and medical supplies.

I cant think of nothing else than:

2 * w ( B + M)

00:00 Uhr, 28.06.2022

$>$ the correct equation of the two you posted was
$>2\cdot A\phantom{\rule{0.12em}{0ex}}=B\phantom{\rule{0.12em}{0ex}}$ because A has twice as much money than B. That is clear

Really? Are you sure? You double the sum owned by A and think thats whats owned by B?
If A owns $200$ $and $B\phantom{\rule{0.12em}{0ex}}$ owns $100$$, then A owns twice as much as B.
Do you really think that $2\cdot A\phantom{\rule{0.12em}{0ex}}=B\phantom{\rule{0.12em}{0ex}}\to 2\cdot 200$ $$=100$$ is correct?
There was a reason I asked you to put in concrete numbers if you are unssure as its a quite common mistake you made.

Don't you think that its rather necessary to double the amount owned by $B\phantom{\rule{0.12em}{0ex}}$ to get the sum which A owns?

$>I\phantom{\rule{0.12em}{0ex}}$ cant think of nothing else than:
$>2\cdot w\phantom{\rule{0.12em}{0ex}}\left(B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}\right)$
Why?????!!!! Thats no equation at all! And what do you think you get when you multiply two numbers (of containers, $W\phantom{\rule{0.12em}{0ex}}$ and $B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}\right)$? I already asked that before.
If we have $10$ conatainerns with water, 4 containers with blood and 6 containers with med supply, what in your opinion is the meaning of $2\cdot 10\cdot \left(4+6\right)$?

I told you in my last reply what you should exchange the A and $B\phantom{\rule{0.12em}{0ex}}$ (or better $X\phantom{\rule{0.12em}{0ex}}$ and $Y\phantom{\rule{0.12em}{0ex}}$ for the reason written in my last answer) for, after you settled for one of the two offered equations.

As you thought that $2\cdot X\phantom{\rule{0.12em}{0ex}}=Y\phantom{\rule{0.12em}{0ex}}$ is correct (which it isn't), you would arrive at $2\cdot W\phantom{\rule{0.12em}{0ex}}=B\phantom{\rule{0.12em}{0ex}}+M\phantom{\rule{0.12em}{0ex}}$. If I remember correct you already offerd this very equation a while ago and because it was wrong we were going through all the hassle with the two guys and their money ;-)

00:47 Uhr, 28.06.2022

Roman, at this point is when I agree with supporter.
at this point you are confusing me more than what you are helping me because you keep talking and talking and talking. you know i dont ost quastion s so you all aanswer them for me without any work or thinking of my own, but if you see me stuck please, get me out!.
if you think I am not getting it after a couple of attempts , man, tell me, for God's sake. I am not getting it. sorry but I am not.
I know it is supposed to have the equal sign but i can not think of nothing else than

the containers of water double the containers for blood and medical supplies combined
i have to write this equation

the word double is here a keyword, i know.

and the thing i am not getting is that therer should be more water than blood and medical supplies. HOW CAN I EQUAL TWO THINGS THAT ARE NOT EQUAL???.

02:12 Uhr, 28.06.2022

It's sad because I get the impression that you don't really read the answers that are given to you. Anyway, you don't answer most of the queries and just try to get the other person to write down the ready answer.

I showed you an easy way by giving a simpler example $\left(X\phantom{\rule{0.12em}{0ex}}$ has twice as much money than $Y\phantom{\rule{0.12em}{0ex}}\right)$ and asked you how to express this with an equation. I also gave you only two equations to choose from and you unfortunately had chosen the wrong one and I told you so. By now at the latest, it should be clear to you that the corresponding equation must logically be the other one, $i\phantom{\rule{0.12em}{0ex}}.e\phantom{\rule{0.12em}{0ex}}$. $X\phantom{\rule{0.12em}{0ex}}=2\cdot Y\phantom{\rule{0.12em}{0ex}},$ and I can only hope that you will at least consider afterwards why this is so.
In any case, this equation is also the crucial point for your task. And I had already written to you $\left(22:30,27.06.2022\right)$ what you should now put in for $X\phantom{\rule{0.12em}{0ex}}$ and $Y\phantom{\rule{0.12em}{0ex}}$ to get the fourth equation for your task that you are looking for $\left(\to$ "you may set $X\phantom{\rule{0.12em}{0ex}}=W\phantom{\rule{0.12em}{0ex}}$ and Y=(B+M)").
Putting that into the simple equation $X\phantom{\rule{0.12em}{0ex}}=2\cdot Y\phantom{\rule{0.12em}{0ex}}$ really shouldn't be that hard, I thought.

What I wanted to prevent from happening here was what has unfortunately often happened with your questions in the past, namely that you thank for a finished solution and declare that you now understand the matter, only to ask a new question a short time later about exactly the same mathematical issue, only because this time it is not the Red Cross but the post office and it is not about water, blood, etc., but about other things. This shows that no understanding has been gained and no learning effect has occurred.

But I realise that it is better not to waste any more of your and my time and I wish you good luck in your undertakings.

03:27 Uhr, 28.06.2022

i got it. thank you
Just think that the people posting here post because they ar not understanding something.
in the past your explanations have been good. i do not know if the language barrier interfered here but you made a mess of it explaining this one. Sorry i have to say this.
i have learned a lot on the site, but you think that for the mere fact that something is explained it needs to be understood. and you're wrong about that. you have wasted precious time and that is what supporter was always telling you all. when you see someone is not getting ti , help him through. just explain the thing. I ALWAYS TAKE NOTES OF THE THINGS YOU ALL SAY.
As soon as you explain the first equation, didn't I do the other two?.

but you did not get it across to me for the last equation. it was your fail, not mine.
if you do not want to help any more, it is okay. thanks for everything, I know this is free and i can't say anything, but I will never quit on someone who wants to learn. never. if you are someone who really loves what you ddo will never quit on someone that tries.

Ich habe es verstanden. Danke.
Ich denke, die Leute, die hier posten, posten, weil sie etwas nicht verstehen.
In der Vergangenheit waren deine Erklärungen immer gut.
Ich weiß nicht, ob die Sprachbarriere hier eine Rolle gespielt hat, aber du hast es bei dieser Erklärung vermasselt. Es tut mir leid, dass ich das sagen muss.
Ich habe auf dieser Website viel gelernt, aber Sie denken, dass man etwas verstehen muss, nur weil es erklärt wird.
Und da liegst du falsch.
Ihr habt kostbare Zeit verschwendet, und das ist es, was die Befürworter euch allen immer gesagt haben.
Wenn ihr seht, dass jemand etwas nicht versteht, helft ihm durch. erklärt ihm die Sache einfach. ICH MACHE MIR IMMER NOTIZEN ZU ALL DEN DINGEN, DIE IHR ALLE SCHREIBT.
Sobald du die erste Gleichung erklärt hast, habe ich die anderen beiden nicht gemacht.

aber bei der letzten gleichung hast du sie nicht klar erklärt. das war dein fehler, nicht meiner.
Wenn Du nicht mehr helfen willst, ist das in Ordnung. Danke für alles, ich weiß, dass es kostenlos ist und ich nichts sagen kann, aber ich werde niemals jemanden aufgeben, der lernen will. niemals. Wenn Du jemand bist, der wirklich liebt, was Du tust, wirst Du niemals jemanden aufgeben, der es versuc

03:32 Uhr, 28.06.2022

i have wrriten 2w = B+ M

according to your last explanation i was almost there
W= 2 * (B + M)

it took you a thousand words to tell me that my reasoning was faulty and i had to move t he 2 to the other side. wow!!!
No, you do me a favor by not helping me anymore. time is precious!.
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