How to measure time Candle Puzzles in Interviews

Candles puzzles is common today in different interviews. Basically we measure given time with 1 or 2 candles. Suppose 1 candles burn in 1 hour. We have 2 candles find out 45 mins with these candles.


How to solve ?
Very simple don't miss these kind of puzzles. Think out of the box and give answer. Above question is very simple.

1 candle fully burns at 1 hour. Now what ?

Lighten first candle from both ends and second candle from just one end. After sometime when first candle burns completely then burn second candle from second end. Thats it.

-> When Burns with Both ends it takes 30mins
-> When Burns from 1 end it takes 1 hour.

-> After burning First candle we had already measured 30mins. Now after burning from second end. We have 30 mins to cross. So it will eventually took 15 mins.

At Last we got 30+15 mins = 45 mins.

 
-> Now measure 90 minutes from these candles ?

Lighten first candle from one side. So it will burn at 1 hour. Now lighten second candle from both ends. So it will take 30 mins. End Up time is 60mins + 30mins =90.

Think like that which comes out very handy for u.

Main thing is never give up attitude