Math Riddle #1(solved)

[Ohio]

Joan and Jane are sisters. Jean is Joan's daughter and 12 years younger than her aunt. Joan is twice as old as Jean. Four years ago, Joan was the same age as Jane is now, and Jane was twice as old as her niece. How old is Jean? How old is her mother? How old is her aunt?

[w0rd]

I cant get this to work..

Lets say Joan = 60
Jean is half that = 30
Jane is 12 years older than Jean = 42
But then Joan is 4 years older than Jane.. when she clearly isnt, 60 - 42 = 18

I give up!

[nita]

well, Jean is Joan's daughter.. that is fact... Joan is four yrs older then Jane, that is fact.

"(four yrs. ago) Joan was the same age as Jane is now, and Jane was twice as old as her niece" <<<<<<< That is leaving it open for her neice to be someone other then Jean.


"Jean is Joan's daughter and 12 years younger than her aunt" <<<<< This could mean alot.. Her could be referring to Jean's Mom Joan or another Aunt of Jean's OTher then Jane.

[z00ey]

let s write it down like this firstbr]
A = Age/years , y = years

(1) A(Jane) = A(Jean) + 12y
(2) A(Joan) = A(Jean) x 2
(3) A(Jane) = A(Joan) - 4y
(4) A(Jane) - 4y = (A(Jean) -4y) x 2

all out of the text ohio gave us.. ..now we look at (1) and (3) and put the right site of both equations into a new, both are equal to A(Jane) ,and getbr](5) A(Jean) +12y = A(Joan) - 4y

now we look at (5) and (2) and getbr](6) A(Jean) +12y = (A(Jean) x 2) - 4y
<==> A(Jean) + 16y = A(Jean) x 2
<==> A(Jean) + 16y = A(Jean) + A(Jean)
<==> 16y = A(Jean)

now that we know that Jean is 16 years old we can just calculate a bitbr]because of (1) Jane must be 28 years old,
because of (2) Joan must be 32 years old..

to prove it we put all into (4) and get 24y = 24y what we can consider as true, lol.. so (if i didn t make a mistake *d**n tired*br]
Jean is 16 years old.
Jane is 28 years old.
Joan is 32 years old.

[Ohio]

Bravo z00ey, well done. You even did it mathmatically instead of by trial and error.

[Alexander]

wow z00ey that looks like an algorythm or something ya just pumped outta c++ , lol

[Fisher]

ive said it before, il say it again...damm germans haha

[z00ey]

lol ;D

..hey at least this is the "maths-board" and not the "guessing-board"

/me notes to code something that autoreplies on alexanders post with "algorYthm" in it.. ..like: "it s algorithm, alexander "
..not that i m a spelling freak (goddam, maybe i am *rimes*) but with "y" it looks so d**n american, muahaha

[Cypher]

yeah zooey did it the way my teacher told me to do these questions. its GCSE (test for 15-16 yr olds) stuff .

[Alexander]

your 16 cypher? . rofl

[Cypher]

nearly as bad as that

17

lol , yeah i know im much to cool , mature and clever to be 17.

im perfect in everyway except im sometimes a bit modest. hehe

[z00ey]

"except im sometimes a bit modest."

hmm..

"except sometimes i m a bit modest"
or
"except i m a bit modest sometimes"


..i ve learned my lessons, mr cypher, lol

[Cypher]

z00ey said:

"except im sometimes a bit modest."

hmm..

"except sometimes i m a bit modest"
or
"except i m a bit modest sometimes"


..i ve learned my lessons, mr cypher, lol

no my word order was fine. its normal in my area.
you ruined my joke lol

[z00ey]

well.. i laughed about it.. ..but i m greedy and thought that i better draw attention away from it ;D


ok ok ok ... read up this thread ppl !!
it IS funny, try to notice it


oh and btw: this is not your area lol ..better try to teach your neighbours about grammar than using them for excuse lol

[Cypher]

haha its so annoying having a german correct me on my english .

well this servers based in california (i think) so we gonna have to talk with a california localisation.

RAD