Processing math: 100%
 
+0  
 
0
879
14
avatar

I am less than 500. All three digits are odd. All three digits are different. The sum of the digits is thirteen. The product of my digits is greater than 30. I am not divisible by 5. Who am I?

 Feb 11, 2016

Best Answer 

 #1
avatar+2499 
+15

 let s say x y z is the digits of your 3 digit number xyz<500x+y+z=13xyz>30i am not divisible by five mean that your number cannot end with 0 or 5so z cannot be 0 and 5 and your number less than 500 so x<5 x can be (3,1): there is only one number: x=1 y=5 z=7 (157)

.
 Feb 11, 2016
edited by Solveit  Feb 11, 2016
edited by Solveit  Feb 11, 2016
 #1
avatar+2499 
+15
Best Answer

 let s say x y z is the digits of your 3 digit number xyz<500x+y+z=13xyz>30i am not divisible by five mean that your number cannot end with 0 or 5so z cannot be 0 and 5 and your number less than 500 so x<5 x can be (3,1): there is only one number: x=1 y=5 z=7 (157)

Solveit Feb 11, 2016
edited by Solveit  Feb 11, 2016
edited by Solveit  Feb 11, 2016
 #8
avatar+298 
+5

397 can't be also the answer as 3+9+7 is 19, not 13, as again mentioned above.

OneDirection  Feb 11, 2016
 #9
avatar+2499 
0

yeah you are right !

Solveit  Feb 11, 2016
 #10
avatar+298 
+5

Told ya. You didn't admit it before.

OneDirection  Feb 11, 2016
 #11
avatar+2499 
0

i was thinking that there is more posibilities :P

Solveit  Feb 11, 2016
 #2
avatar+298 
+10

You are a human being, duh.

Now don't expect me to write your name.

Still, I think the answer is 157.

 Feb 11, 2016
 #3
avatar+298 
+5

But SolveIt, 3x9x1 is 27, which is not greater than 30, as mentioned above.

 Feb 11, 2016
 #5
avatar+2499 
0

wait .... :)

Solveit  Feb 11, 2016
 #7
avatar+2499 
0

hooh

Solveit  Feb 11, 2016
 #4
avatar+4084 
+5

LMAO, 1D! :D

 Feb 11, 2016
 #6
avatar+298 
0

What? I'm just telling the truth, but wait.....there may be 0.00000001% chances he might be an extra terrestial body, plus I gave him the answer too.

 Feb 11, 2016
 #12
avatar+298 
+5

There may be, but I don't wanna try as I have to go out.

 Feb 11, 2016
 #13
avatar+130477 
+5

Nice work, OneDirection and Solveit.....points from me.....!!!

 

Here's  a way to confirm this......

 

x + y + z  = 13

x * y * z > 30

 

Now ....assume z = 9.....but this means that x and y could only be 1 and 3  since 1 + 3 + 9 = 13......but 1 * 3 * 9  = 27

 

And that's < 30

 

So......let's assume that  z = 7

 

So  z = 13 - x - y  →  7  = 13 - x - y  →   x + y   = 13 - 7  →  x + y  = 6

 

Thus.....either x = 1 and y = 5   or   vice-versa

 

So......if we write the number as xyz, the only possibility is  xyz  =  157

 

 

 

cool cool cool

 Feb 11, 2016
 #14
avatar+26397 
+5

I am less than 500. All three digits are odd. All three digits are different. The sum of the digits is thirteen. The product of my digits is greater than 30. I am not divisible by 5. Who am I?

 

(1)x+y+z=13z=13(x+y)(2)x100+y10+z<500x100+y10+13(x+y)<50099x+9y+13<5009y<99x+500139y<99x+487 y < 11x+4879 (3)xyz>30xy>30z xy > 3013(x+y) 

 

I have put  y < 11x+4879 and  xy > 3013(x+y) in https://www.desmos.com/calculator
se we have a result of 5 Points. see:

 

Now let us see:

xyz=13(x+y)result1513(1+5)=7yes1713(1+7)=5no, because  175  is divisible by  53313(3+3)=7no, because  x=y3513(3+5)=5no, because  y=z3713(3+7)=3no, because  x=z

 

There is only one number 157

 

laugh

 Feb 12, 2016

2 Online Users

avatar