Joe's Age
Math brain teasers require computations to solve.
Joe's age plus 3 is a square number
Joe's age minus 3 is the square root
What is Joe's age?
Answer
Joe is 6 years old
6 + 3 = 9
6  3 = 3
3^2 = 9
Hide
Comments
BadBunnee02
Jul 29, 2014
 OK
Brandnew teaser.
Credible. Fitting. Challenging.
How many comments?
Any bets?
I'll say ..................... fewer than five.
(not, of course, counting this one).
(that way I can't be accused of "influencing" the results) ....
So, you can lower your finger (the one that's poised over the "offensive" button).
Oh ... you folks are so much FUN !!!!!!!
YLADS (as ever)
BB02 
Gizzer
Jul 29, 2014
 Very simple. It would have benefitted from a story to add some fun. 
BadBunnee02
Jul 30, 2014
 Sorry, Ghosty ......
Should have had higher rankings and ....
FIFTY !!!!!!!!!!!!!!!!!!!!
... comments.
But ..... everybody sez the reason is because I ... I ... I ... I... (as in ME) is here.
"Scaring" everybody off.
Do you believe that?
WHAT a bunch of C * * P.
There are other reasons why participation is so low, and we had better find them out and correct them or .....................
Braingle is DEAD DEAD DEAD
BB02 
BadBunnee02
Jul 30, 2014
 2
2
2
2
2
2
That's right, folksies ...
TWO ....
A NEW Teaser comes and goes ... and we get ... TWO comments for the first day.
And some of you DARE to say
"all is well" .... and
accuse me of "sky is falling" tactics AND .....
Have me censured (loss of Karmas and privileges) ............
Proud of yourselves ????
BB02 
BadBunnee02
Jul 30, 2014
 Here I am ...
your NAKED "protest" ... "ant" ....
(what did you expect .... hmmmmm ??)
BB02 
BadBunnee02
Jul 30, 2014
 Perhaps an explanation would help.
I am a protestant (protest ... er) concerning the condition and health of Braingle. I protest about it, a LOT.
I am "naked" as in .... "devoid" ... (without, don't have, missing, etc.)
of defences or friends.
I'm doing it all by myself. Not a SINGLE other Braingle participant has "stepped up" to assist me.
But .... guess what?
I expected that.
Because a person in a "state of denial" will often "deny" that the "denial" even exists.'
Look in a mirror (some of you) ... if you want to see one.
YLADS (as ... always)
BB02 
HABS2933
Jul 31, 2014
 Easy enough for Joe to solve it. 
eighsse
Jul 31, 2014
 the given answer is easy. But did anyone find the other answer?
Joe can also be 1.
1 + 3 = 4
1  3 = 2
(2) ^ 2 = 4 
eighsse
Jul 31, 2014
 Simple to see when you set it up algebraically.
x is Joe's age.
(x  3)^2 = x + 3
x^2  6x + 9 = x + 3 (expand left side)
x^2  7x + 6 = 0 (subtract right side from left side)
0 = (x  6)(x  1) (factor left side, and reverse)
The two solutions to zero the right side, forming a true statement are 6 and 1. 
BadBunnee02
Jul 31, 2014
 Excellent analysis & explanation ... eighssee ...
WELL DONE !!!!!
BB02 
Jimbo
Nov 20, 2014
 The way the teaser is phrased it says square root which is positive by definition. Therefore 1 is not an additional answer since sqrt(4) = 2 (not 2). 
addspras
May 09, 2015
 answer can be 6 or 1; @jimbo: sq rt of 4 is 2 or 2 
eighsse
May 09, 2015
 Jimbo is actually correct. I had never been taught that "square root" specifically meant the positive. But then, what do you call it to mean + or ? Just "second root" or what? 
mnkgyl
May 10, 2015
 2^2=4
(2)^2=4
But
√4=2
√4=2 
eighsse
May 11, 2015
 So I guess the disconnect shows, for example, when you are solving an algebraic equation, like so:
x^2 = 4
{take "square root" of both sides}
x = +/ 4
WRONG!
x^2 = 4
{(1) take square root of both sides}
x = 4
{(2) OR, take negative square root of both sides}
x = 4
RIGHT! 
theriddler
Jul 16, 2015
 I also got one as the age. I was thinking of bringing this to my group I do riddles withthey gave me the name "the riddler"but I modified it following Gizzer's suggestion. So it begins, "Joe is learning about square roots. Being the type of kid that thinks about things a lot, he notices his age plus three is a square number, and his age minus three is the square root." OK, Six is young to learn about square root, but I know someone who was doing them at five. I like the story settingthanks for the suggestion, Gizzerand it makes the answer "one" less likely. 
Back to Top
 
