HardMath and Logic
Two 1-hr ropes, burn inconsistently. Measure 45 mins?
Riddle
Two 1-hr ropes, burn inconsistently. Measure 45 mins?
Choose an answer
A.Light one end and wait
B.Cut one in half
C.Light one at 15m
D.Light ends of R1, 1 end of R2
Hint: It's a 7-word phrase with 18 letters, starting with "L".
Answer
Light ends of R1, 1 end of R2
Why this is the answer
Lighting both ends of a 60m rope makes it burn in 30m. By lighting one end of Rope 2 at the same time, it has 30m left when Rope 1 finishes. Lighting its other end then gives 15m.
This riddle is filed under Expert Riddles for Adults and rated Hard.
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