Time's up noobs. Nobody got it so I win. Now, here's what your solution should look like:
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To begin with, let's set some variables for their numbers.
a=1, b=2, c=3, d=4, e=5, f=6, g=7, h=8, x=9, y=0 (with x and y because any maths problem respecting itself should contain x and y)
For example, a≠1 since it is equal to their 1, which is not equal to our 1. I hope I'm not making it too complex already.
Now, let's see what the problem gives us.
4 × 7 = 28
5 × 7 = 35
4 × 6 = 24
1 + 4 + 6 + 7 + 7 = 25
Which can be now transformed to:
d × g = 10b + h (1)
e × g = 10c + e (2)
d × f = 10b + d (3)
a+d+f+2g = 10b+e (4)
(From now on, I'll omit the "×" symbol so that you don't confuse it with the x variable. "d × g" is now "dg".)
Now the only way to move on is to assign random values to one of the variables. I've chosen b, after having tried with d and g first. b seems to be the correct choice, but I'm not sure, it may be solvable if you choose one of the others as well. So, let's go:
- b=0
Equation (3) ⇒ df=d
And since d≠0 (since b=0 and not two variables can have the same value), we get f=1.
Equation (4) ⇒ a+d+1+2g=e
The lowest possible value of "a+d+1+2g" is for g=2, d=3 and a=4.
This means 4+3+1+4=e ⇒ e=12 which can't be right since e is between 0 and 9.
- b=1
Equation (3) ⇒ df=10+d ⇒ d(f-1)=10
Which means that either d=2 and f-1=5⇒f=6 which is wrong since f≠6 as we said in the beginning, or d=5 and f-1=2⇒f=3
Equation (4) ⇒ a+5+3+2g=10+e ⇒ a+2g=2+e ⇒ 10g=10-5a+5e (5)
Equation (1) ⇒ 5g=10+h ⇒ 10g=20+2h (6)
According to (5) and (6), 10-5a+5e=20+2h ⇒ 2h=5(e-a-2)
I'm bored to elaborate more on this, but the last equation will end in impossible equations in any case, so the whole thing was wrong which means b≠1.
- b=2, which is wrong since b≠2 according to the problem.
- b=3
Equation (3) ⇒ df=30+d ⇒ d(f-1)=30
Which means that either d=6 and f-1=5⇒f=6 which is wrong because they get the same value, or that d=5 and f-1=6⇒f=7
Equation (1) ⇒ 5g=30+h ⇒ h=5(g-6)
Since h<10, its only possible values are h=5 and h=0 (since the second part of the equation is multiplied by 5). But h≠5 since d=5. So, h=0, which means g-6=0⇒g=6
Equation (4) ⇒ a+5+7+12=30+e ⇒ a=e+6 which means that a>6. But a≠7 since f=7 and a≠9 since then e=3 which is wrong since b=3. So, a=8 and e=2.
Equation (2) ⇒ 12=10c+2 ⇒ c=1
So, the only variables remaining are x and y and the only values remaining are 4 and 9. But x≠9 according to the problem, so x=4 and y=9
- In any other case (b=4, b=5, ... , b=9), you'll end in impossible results, which I'm bored to type.
So, to sum up. What they have as 1234567890, we've got it as 8315276049
Which means that their 2×302 equals our 3×193=579 and our 579 equals their 460. So the final result is
2×302=460.
Should you know Greek and are bored to read this, I've scanned my solution, click
here for it.
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Fr3quency obviously googled the result so he didn't get it.
I'll post a new challenge when I find a cool, worthy one.
Also note that the above solution was not copy-pasted from some random site, I typed it myself, copying the solution I had in paper (the scan) which was in Greek. If someone doubts about it, I don't really care.