Question: Can you break down the solution for me for this math problem: John drinks a bottle of water every half hour.  A normal sudoku puzzle takes him 45 minutes.  An extreme sudoku takes 4 times that long.  How many bottles of water does he drink in that time?
Answer: 
He drinks a bottle of water every 60/2=30 minutes
It takes him 45*4=180 minutes to solve an extreme sudoku
So he drinks 180/30=6 bottles in that time