A jar contains a certain number of cookies. If 25%

[actleader]

Question from GoGMAT:

A jar contains a certain number of cookies. If 25% of the cookies are removed, the jar is half empty. If 100 cookies are added, the jar is full. How many cookies are there in the jar?

the answer, which is provided is 200
the algebraic solution is following :
1. if 25% of the cookies are removed, the jar is half empty, this means that 0.75C=T/2.
2. if 100 cookies are added, the jar is full, so C+100=T.

But,
If the number of cookies is 200 then 25% of 200 is 50,
having removed 50 cookies out of 200 we have 150 (according to the problem - half of the jar's capacity).
So the capacity of the jar is 300.

Nevertheless, 150+100=250 which does not equal 300 so the solution can't be 200?

[tim]

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