Math problem

TarfHead

Registered User
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As part of a treasure hunt type activity, we were given an equation and told to find the values for A through E to solve for X

X = (B/D) + (A*B*D) - ((C*C) - (B*E)) - E + (D*D)

The values we obtained were as follows.
A 3
B 8
C 18
D 2
E 20

Using these values, we get an answer of -128. The answer expected was in the range 30 to 32, and we were later advised that the correct answer is 31.

My question is ..

Can one or more of these (A through E) values be changed to get X = 31 ?
 
Aaah (smacks palm of hand against forehead )

That's great, thanks for the help.
 
I don't understand how you came up with b=14?

You can set up the formula in Excel and use the goalseek function (to get X=31) varying each of a, b, c, d & e one by one. Each has a solution but b was the only integer solution.

Would be much trickier if more than one of the variables was incorrect!
 
You can set up the formula in Excel and use the goalseek function (to get X=31) varying each of a, b, c, d & e one by one. Each has a solution but b was the only integer solution.

Interesting, I didnt know you could do that in Excel.
 
What details were you given intially? Were you just given this formula, and the fact that 29 < x < 33?
 
What details were you given intially? Were you just given this formula, and the fact that 29 < x < 33?

It was not a given (29 < x < 33), just an assumption based on other information. I could go into further detail, but it's quite dorky / nerdy .

There were other equations for other answers. We knew that if we could solve X correctly, the others would work out OK too.
 
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And it wasnt nerdy of me to go off and manually work out the answer!! Im insulted! I thought my geek factor had much higher visibility!

Do enlighten us, some of us like nerdy stuff.
 
Do enlighten us, some of us like nerdy stuff.

It was a treasure hunt type activity (geocaching if you're interested).

The X value was the part of a GPS co-ordinate for the north county Dublin. We assumed (correctly as it turned out) to be somewhere between Rush and Balbriggan; the 'hunt' stated near Skerries.

We reckoned the location would be somewhere between N 53 28.000 (Malahide / Donabate) and N 53.37.000 (Balbriggan). For this to be true, X needed to be in the range 28 to 37, e.g. location was given as N 53 X.YZ

Glad you asked ?

And, yes, I know I haven't given the West co-ordionates. That would be overkill !