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 July 15th, 2017, 10:58 AM #1 Newbie   Joined: Dec 2010 Posts: 19 Thanks: 0 A tricky question When I first see this, I just doubt there's a solution. But actually it has a solution. Anyone wanna try this? A man has 3027 STR points. He takes a potion and has a pet. The potion adds 25% of all points. (count as add-on X) The pet adds 6% of all points. (count as add-on Y) The calculation of the potion includes the Y. The calculation of the pet includes the X. What value is X and Y? You can round it to the nearest tenth. Last edited by Kavesat; July 15th, 2017 at 11:16 AM.
July 15th, 2017, 12:03 PM   #2
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Quote:
 Originally Posted by Kavesat When I first see this, I just doubt there's a solution. But actually it has a solution. Anyone wanna try this? A man has 3027 STR points. He takes a potion and has a pet. The potion adds 25% of all points. (count as add-on X) The pet adds 6% of all points. (count as add-on Y) The calculation of the potion includes the Y. The calculation of the pet includes the X. What value is X and Y? You can round it to the nearest tenth.
it's tough to understand exactly what you mean here but it sounds like you have

$FSTR=3027 + X + Y = 3027 + 0.25 FSTR + 0.06 FSTR$

$FSTR = 3027 + 0.31 FSTR$

$0.69 FSTR = 3027$

$FSTR = \dfrac{3027}{0.69}$

$X = \dfrac{0.25}{0.69}\cdot 3027 \approx 1096.7$

$Y = \dfrac{0.06}{0.69}\cdot 3027 \approx 263.2$

July 15th, 2017, 01:17 PM   #3
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 Originally Posted by romsek it's tough to understand exactly what you mean here but it sounds like you have $FSTR=3027 + X + Y = 3027 + 0.25 FSTR + 0.06 FSTR$ $FSTR = 3027 + 0.31 FSTR$ $0.69 FSTR = 3027$ $FSTR = \dfrac{3027}{0.69}$ $X = \dfrac{0.25}{0.69}\cdot 3027 \approx 1096.7$ $Y = \dfrac{0.06}{0.69}\cdot 3027 \approx 263.2$
Well, it seems wrong because if you try to check calculation.
(1096+3027)*0.06=247
It doesn't correspond with the pet Y 263
As the statement says,
The calculation of the potion includes the Y.
The calculation of the pet includes the X.
There is actually a value that can correspond with each other.

Last edited by Kavesat; July 15th, 2017 at 01:21 PM.

 July 15th, 2017, 02:58 PM #4 Global Moderator   Joined: Dec 2006 Posts: 19,162 Thanks: 1638 If the problem means that X = 25% of (3027 + Y) and Y = 6% of (3027 + X), it's easy to solve those to get X = 814.4 and Y = 230.5 (both rounded to the nearest tenth of a point).
July 15th, 2017, 04:59 PM   #5
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 Originally Posted by skipjack If the problem means that X = 25% of (3027 + Y) and Y = 6% of (3027 + X), it's easy to solve those to get X = 814.4 and Y = 230.5 (both rounded to the nearest tenth of a point).
Yes, you got it.
It is still somewhat tricky because in practice if you want to try to measure something X (like the potion) that is related to something Y (pet), but the Y can't be determined itself value because it requires to know the X's value FIRST, then you can't calculate the X, either. That's why I first time encountered this and confused for a while without thinking deeply of using equations.

My previous calculation:

3027 +x
x is x

(3027 +x)*0.06= y

[3027+(3027 +x)*0.06]*0.25=x
[3027+181.62+0.06x]*0.25=x
[3208.62+0.06x]*0.25=x
802.155+0.015x=x
x=814.370558376~814.4
y=230.482233503~230.5

Last edited by skipjack; July 17th, 2017 at 03:19 AM.

July 15th, 2017, 06:17 PM   #6
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Quote:
 Originally Posted by Kavesat It is still somewhat tricky because in practice if you want to try to measure something X (like the potion) that is related to something Y (pet), but the Y can't be determined itself value because it requires to know the X's value FIRST, then you can't calculate the X, either.
Try something similar but simpler; as example:
price before discounts: 1000
1st discount: 20%
2nd discount: 10% of (1000 - 20%)
net: ?

Your problem can be solved similarly.

Last edited by skipjack; July 17th, 2017 at 03:20 AM.

July 17th, 2017, 02:34 AM   #7
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Quote:
 Originally Posted by romsek it's tough to understand exactly what you mean here but it sounds like you have $FSTR=3027 + X + Y = 3027 + 0.25 FSTR + 0.06 FSTR$ $FSTR = 3027 + 0.31 FSTR$ $0.69 FSTR = 3027$ $FSTR = \dfrac{3027}{0.69}$ $X = \dfrac{0.25}{0.69}\cdot 3027 \approx 1096.7$ $Y = \dfrac{0.06}{0.69}\cdot 3027 \approx 263.2$
Sorry, my bad. I reread all replies. My statement is not clear. I shouldn't use "all points" to misguide you.
In the case of "all points" to calculate each single includes x and y, you are right. Your calculation is brilliant.
And I am still a bit surprised that it still can be "calculated" in that case and if there is a case like that in reality.

Quote:
 Originally Posted by Denis Try something similar but simpler; as example: price before discounts: 1000 1st discount: 20% 2nd discount: 10% of (1000 - 20%) net: ? Your problem can be solved similarly.
Hmm, it looks like it can be calculated directly without worrying about the other variable.

Last edited by skipjack; July 17th, 2017 at 03:21 AM.

July 29th, 2017, 04:36 AM   #8
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Quote:
 Originally Posted by Kavesat It is still somewhat tricky because in practice if you want to try to measure something X (like the potion) that is related to something Y (pet), but the Y can't be determined itself value because it requires to know the X's value FIRST, then you can't calculate the X, either. That's why I first time encountered this and confused for a while without thinking deeply of using equations.
That is exactly the kind of problem algebra is intended to solve.

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