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1 5
M _ N _ T _ S
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_ L _ P S _ D Clue
LET'S NAME THE ROPES AS A AND B. LIGHT A FROM BOTH THE ENDS AND B FROM ONE END. WHEN A IS FINISHED BURNING WE KNOW THAT 30 MINUTES HAVE ELAPSED AND B HAS 30 MINUTES REMAINING. NOW, LIGHT THE OTHER NON-BURNING END OF B AND START THE TIMER. WHEN B IS FINISHED BURNING, STOP THE TIMER AS 15 MINUTES HAVE ELAPSED THE STUDENT IS DOUBLE COUNTING A LOT OF THE DAYS. A LOT OF THE TIME SPENT SLEEPING, EATING, AND RELAXING OCCURS DURING WEEKENDS AND THE SUMMER. WEEKENDS ALSO OCCUR DURING THE SUMMER, SO ALL OF THESE HOURS ARE GETTING COUNTED SEVERAL TIMES. AND, SCHOOL IS NOT AN ALL DAY AFFAIR. SO THE 4 DAYS ACTUALLY REPRESENTS MORE DAYS OF SCHOOL. IF SCHOOL IS 6 HOURS PER DAY, THOSE FOUR DAYS REPRESENTS 16 DAYS OF SCHOOL YOU WILL HAVE TO LIE AWAKE FOR 1 HOUR TO BE SURE OF THE TIME. THE STRIKE YOU HEARD WAS EITHER 1:00 AM OR SOME HALF HOUR. IF, AFTER ANOTHER HALF HOUR YOU HEAR TWO OR MORE STRIKES, YOU KNOW WHAT HOUR IT IS, BUT IF YOU AGAIN HEAR ONE STRIKE, YOU MAY HAVE HEARD SUCCESSIVELY 12:30 AM AND 1:00 AM OR 1:00 AM AND 1:30 AM. AFTER ANOTHER HALF HOUR YOU EITHER HEAR 1 STRIKE (1:30 AM) OR TWO STRIKES (2:00 AM) THERE ARE TWO POSSIBLE SOLUTIONS (AND MAYBE MORE). SOLUTION 1: LIE THE CANDLES HORIZONTALLY NEXT TO EACH OTHER, BUT WITH THE WICKS AT OPPOSITE ENDS. LIGHT BOTH THE CANDLES. WHEN THEY MEET, THEY'LL HAVE BOTH BURNED HALFWAY - 30 MINUTES GONE. NOW BLOW ONE OUT. LET THE OTHER BURN THE REST OF ITS 30 MINUTE LIFESPAN - NOW YOU'VE TIMED 60 MINUTES. WHEN IT GOES OUT, RELIGHT THE OTHER ONE FOR THE REMAINING 30 MINUTES - TOTAL OF 90 MINUTES. SOLUTION 2: FIRST LIGHT UP THE TWO ENDS OF THE FIRST CANDLE. WHEN IT HAS FULLY BURNED, LIGHT UP ONE END OF THE SECOND CANDLE. FIRST CANDLE TAKES 30 MINS TO BURN OUT AND SECOND CANDLE WILL TAKE 60 MINS - TOTAL OF 90 MINUTES