Simple Puzzle: A Matter Of Time I am trying to solve a simple puzzle:
Fifty Minutes ago if it was four times as many minutes past three O'clock, how many minutes is it to six O'clock.
I tried solving it:
Let x be the minutes past 5,
then 120 + x - 50 = 4x 
which gives the wrong answer.
The correct solution has the formulation 180 - 50 -x = 4x which gives x = 26 and is the correct answer.
Am I doing weird thing by assuming that x is the minutes past 5 ? My approach is same as the one with correct solution if I use 4(60 -x) on the LHS but why should I ?
Is it that the puzzle is wrong in its formulation or am I missing something and hence am unable to arrive at the correct solution ? 
By the way, the puzzle is from a famous book by Shakuntala Devi and hence I am forced to doubt the validity of my approach.

Because the time until $6$ is not the same as the time past $5$, treating $x$ this way results in a solution that is based on a false assumption. To remedy this, you would want to re-write the RHS to match with how you have written the LHS.
In order to avoid algebraic acrobatics, consider the problem as such: the "goal" time is $6$, which is $180$ minutes after $3$, but it is presently $x$ minutes prior to $6$. This gives us the $180-x$. Then we have that $50$ minutes ago, it was $4$ times longer after $3$ than it is presently before $6$, and this gives us the $-50$ and the $4x$.
Hence the book's set up is correct. The BIG problem is that the problem has a confusing wording. It would be easier to say: "If the time 50 minutes ago was 4 times as many minutes past three as the time now is before six, then what time is it now?"
