Posted by kaykay on Friday, April 22, 2011 at 6:37pm.
Please check if there is a typo.
It is not possible that after Connor gave more than half of his money to Luisa and they still have an equal amount... unless Luisa had a negative amount (i.e. owes money) to start with.
yes there is a typo it's supposed to be that he gave her 2/5 of his money.
KayKay -- please check the links below the Related Questions.
I don't understand those answers and wanted to see of anyone explained it differently.
Start by writing down what we know.
--There is $360 between two people.
--The names of the two people are Connor (which we will now call "C") and Luisa (we will call her "L").
--C gave L 2/5 of his money. They then had the same amount of money.
So let's break it down into what we can write for math. Since they both have $360, we can say if we add C and L's money together, there is $360.
C+L=360
We also know that if C gives L 2/5 of his money, they will have the same amount.
So L gets 2/5 of C's money.
L + 2/5C
That is equal to C losing 2/5 of his money (since he gave it to L)
C - 2/5C
Since they are now the same, we can put them together and say they are equal.
L + 2/5C = C - 2/5C
Now we have 2 equations:
L + 2/5C = C - 2/5C
AND
C+L = 360
Now what we want to do is put one letter by itself in any equation. (2nd one is easier to do).
C + L = 360
L = 360 - C
Now we can take that and change out the "C" in the other equation:
L + 2/5C = C - 2/5C
Anywhere we see a "L" we will change it to "360-C"
360-C + 2/5C = C - 2/5C
Now we just have to get C by itself.
360 = C - 2/5C + C - 2/5C
360 = 2C - 4/5C
360 = 1 1/5C
360 = 6/5 C
300 = C
So we know C had $300
The only question now is how much did L have?
Remember "C + L = 360?"
Since C had $300, we can say
300 + L = 360
L = 60
So C had $300
L had $60
Now we can check. C gave L 2/5 of his $$
300(2/5) = $120.
So C gave L $120, leaving him with $180.
L got $120. She had $60. So L NOW has $180
They both have the same amount.
Hope that helps. :-D