Very difficult IQ problem

[stinkynuts]

1 @ 9 = 0
3 @ 8 = 18
9 @ 8 = 72

9 @ 9 = ?


If you know the answer for sure, please don't post it. Instead, just say that you solved it. That way others can try, thanks.

 

[CUPID]

1 @ 9 = 0
2 @ 9 = 8
9 @ 8 = 72

9 @ 9 = ?


If you know the answer for sure, please don't post it. Instead, just say that you solved it. That way others can try, thanks.

Solved.

 

[stinkynuts]

Solved.

The original problem had an error in it, so your solution is probably incorrect.

 

[Sabiha]

1 @ 9 = 0
3 @ 8 = 18
9 @ 8 = 72

9 @ 9 = ?


If you know the answer for sure, please don't post it. Instead, just say that you solved it. That way others can try, thanks.

kind of a weird question? if you assume @ means multiplied by, the answer to 9@9 is 81, where 1=0 and 3=2.25.

 

[oldjones]

Why would the 'at' sign mean anything more than 'at'? And where can 1=0? 'One is one and all alone and evermore shall be so' . Stinky is quite capable of confusing us without help from others.

 

[stinkynuts]

The @ sign is an arbitrary symbol for an operation.

For example 3 @ 5 = 20.

Here @ means take the first operand (3) and multiply by the second operand (5), and then add the second operand (5).

So 2 @ 5 = 2 * 5 + 5 = 15

Why would the 'at' sign mean anything more than 'at'? And where can 1=0? 'One is one and all alone and evermore shall be so' . Stinky is quite capable of confusing us without help from others.

 

[stinkynuts]

If you want your answer validated, pm it to me. So far it seems no one has cracked this problem. Once the answer is known, it is incredibly easy.

 

[myfuntime]

why don't you post answer. we can read, try and scroll down to see and match...

 

[stinkynuts]

So far only one person has pm'ed me with the correct answer.

 

[james t kirk]

80

If the pattern is correct as posted above.

 

[rhuarc29]

I hate IQ questions like this because there are multiple solutions.

For example, if you (1) multiple the two numbers together, (2) subtract the 2nd from the sum, (3) divide by 8, and (4) multiply by 9, then:

1 @ 9 ----------------> 1 * 9 = 9 - 9 = 0 / 8 = 0 * 9 = 0
3 @ 8 ----------------> 3 * 8 = 24 - 8 = 16 / 8 = 2 * 9 = 18
9 @ 8 ----------------> 9 * 8 = 72 - 8 = 64 / 8 = 8 * 9 = 72

Which would make:

9 @ 9 ----------------> 9 * 9 = 81 - 9 = 72 / 8 = 9 * 9 = 81

That solution works, but I'm sure I got the "wrong" answer, right?

 

[afx]

I too got the "wrong" answer, but my logic works too. Stupid question with multiple answers.

1@9=0

The rule to use is simple. You multiply the first digit (in this case, a 1) by "9". You then take the sum of the digits of this product. In the case, since the product is 9, the sum of the product is just 9. You take this number, and subtract the second number from it. In this case, we get 9-9=0. Save this number (lets call it "correction factor").

Then use the rule 9* first number minus second number minus the correction factor.

Therefore we get 9 * 1 - 9 - 0 = 0

for 3@8=18, the final equation would be 9 * first number minus second number minus the correction factor.

The correction factor is simply the first digit times 9, which is 27. We take the sum of the digits of this product which is 9. We then subtract the second number from it, which is 8. The correction factor is 1.

Therefore we get 9 * 3 - 8 - 1 = 27 - 8 - 1 = 18

9@8=72, the final equation would be 9*9-72-correction factor, where correction factor is 9*9 = 81, sum of products is 9 subtract 8 from it to get 1

Therefore we get 9*9-8-1 = 72

Therefore for 9@9=81, the correction factor is 9*9=81, sum of digits is 9, subtract 9 from it you get 0. So equation is 9*9-9-0 = 72

 

[adickson]

I got 80 as well as in this pattern where @ is a function with two operands as input
(1-1) x (9+1)=0
(3-1) x (8+1)= 18
(9-1) x (8+1) = 72
(9-1) x (9+1) = 80
if this is correct, this is just grade 3 math, not really an IQ question, unless the answer is wrong, of course.

 

[rhuarc29]

I got 80 as well as in this pattern where @ is a function with two operands as input
(1-1) x (9+1)=0
(3-1) x (8+1)= 18
(9-1) x (8+1) = 72
(9-1) x (9+1) = 80
if this is correct, this is just grade 3 math, not really an IQ question, unless the answer is wrong, of course.

I believe that is the "correct" solution...

 

[papasmerf]

I got 80 as well as in this pattern where @ is a function with two operands as input
(1-1) x (9+1)=0
(3-1) x (8+1)= 18
(9-1) x (8+1) = 72
(9-1) x (9+1) = 80
if this is correct, this is just grade 3 math, not really an IQ question, unless the answer is wrong, of course.

Fact is the first 3 examples are wrong

They were posted wrong and never corrected.

 

[TVA]

I think both rhuarc29 and adickson solutions are correct. there might be millions or even infinate number of possible solutions. the really hard questions to ask is how many possible solutions to fit the first 3 examples.

 

[Mitch]

The @ sign is an arbitrary symbol for an operation.

For example 3 @ 5 = 20.

Here @ means take the first operand (3) and multiply by the second operand (5), and then add the second operand (5).

So 2 @ 5 = 2 * 5 + 5 = 15

Given this example I take it the answer should be in the form a @ b = c...other numbers should not be brought in to the equation.

I came up with:

(a-(a/a))*(b+b/b) = c
(1-(1/1))*(9+9/9) = 0
(3-(3/3))*(8+8/8) = 18
(9-(9/9))*(8+8/8) = 72
(9-(9/9))*(9+9/9) = 80

There probably are other solutions…

 

[GPIDEAL]

If you want your answer validated, pm it to me. So far it seems no one has cracked this problem. Once the answer is known, it is incredibly easy.

So you don't have to specify what the arbitrary @ symbol's operation is? Just look at the results stated in the examples for a pattern.

 

[GPIDEAL]

kind of a weird question? if you assume @ means multiplied by, the answer to 9@9 is 81, where 1=0 and 3=2.25.

Generally, '@' does mean multiply, but not sure yet in this case.

If 1 = 0, and 3 = 2.25, why would the first 9 in the equation be the number 9?

 

[rhuarc29]

Given this example I take it the answer should be in the form a @ b = c...other numbers should not be brought in to the equation.

I came up with:

(a-(a/a))*(b+b/b) = c
(1-(1/1))*(9+9/9) = 0
(3-(3/3))*(8+8/8) = 18
(9-(9/9))*(8+8/8) = 72
(9-(9/9))*(9+9/9) = 80

There probably are other solutions…

Good point.

a * b + a - b - a / a = c
1 * 9 + 1 - 9 - 1 / 1 = 0
3 * 8 + 3 - 8 - 3 / 3 = 18
9 * 8 + 9 - 8 - 9 / 9 = 72
9 * 9 + 9 - 9 - 9 / 9 = 80

Although, if you know anything about quadratic equations and factoring you'd realize my new answer is a little redundant...do I still win?