Math Is Fun Forum

KerimF

Member

From: Aleppo-Syria

Registered: 2018-08-10

Posts: 241

Transporting fuel

A city has 13,500 litres of fuel in excess to be sent to another city in need at a distance of 450 miles.
The capacity of the available transport tank is 4500 litres and it consumes 10 litres/mile.
It is possible to use fuel reservoirs at many locations on the road as necessary.

The question is:
What is the maximum quantity of fuel that could be delivered at the second city?

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Every living thing has no choice but to execute its pre-programmed instructions embedded in it (known as instincts).
But only a human may have the freedom and ability to oppose his natural robotic nature.
But, by opposing it, such a human becomes no more of this world.

KerimF

Member

From: Aleppo-Syria

Registered: 2018-08-10

Posts: 241

Re: Transporting fuel

I heard of this problem in early 80’s from a person returning from France. He told me that it was a question in a context TV show (French) that couldn’t get an answer. After about 40 years, I am not sure what its original numbers were but I still remember how I solved it. Its few equations have each one variable (unknown) of the first degree.

For instance, when I was a student and before starting a math exam, I noticed a colleague in my classroom trying, in vain, to solve an exercise that was expected to be given in the exam. I thought that helping him is a good thing. So I reminded him the basic hint by which the exercise in question could be solved rather easily. He looked at me and said: “Who asked you for help? I bet you are happy now for proving you are smarter than I”. So I apologized, but since then I fully understood the famous saying “Ask and you will be given” which also means “Give if you are asked... otherwise don’t blame the other side for any unexpected reaction”

---

Every living thing has no choice but to execute its pre-programmed instructions embedded in it (known as instincts).
But only a human may have the freedom and ability to oppose his natural robotic nature.
But, by opposing it, such a human becomes no more of this world.

KerimF

Member

From: Aleppo-Syria

Registered: 2018-08-10

Posts: 241

Re: Transporting fuel

The answer is:
The maximum quantity of fuel that could be delivered at the second city is 2400 litres.

---

Every living thing has no choice but to execute its pre-programmed instructions embedded in it (known as instincts).
But only a human may have the freedom and ability to oppose his natural robotic nature.
But, by opposing it, such a human becomes no more of this world.