YOU SHOULD KEEP ME AS STRAIGHT AS CAN BE YET VERY FEW DO MOST OF THE TI RIDDLES WITH ANSWERS TO SOLVE - PUZZLES & BRAIN TEASERS

Let us denote the four people with A, B, C and D.
A takes 1 minute to cross, B takes 2, C takes 5 and D takes 10.

A and B cross first spending 2 minutes.
A comes back with torch taking 1 minute.
C and D cross taking 10 minutes.
B comes back with torch taking 2 minutes.
Finally, A and B cross the bridge taking 2 minutes.

2 + 1 + 10 + 2 + 2 = 17 minutes

Thus, this is the way they all managed to cross that bridge that night. Did you answer this riddle correctly?
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Sheep Did you answer this riddle correctly?
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A Pen-Guin! Did you answer this riddle correctly?
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A clock! Did you answer this riddle correctly?
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The faster watch gains on the slower one at the rate of three minutes every hour. After 20 hours, the faster one will be ahead by one hour. Did you answer this riddle correctly?
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A clock Did you answer this riddle correctly?
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Your kneecap! Did you answer this riddle correctly?
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Air conditioner Did you answer this riddle correctly?
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Benjamin Banneker Did you answer this riddle correctly?
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Refrigerator Did you answer this riddle correctly?
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Refrigerator Did you answer this riddle correctly?
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A window Did you answer this riddle correctly?
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Its a stapler Did you answer this riddle correctly?
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The mermaid Did you answer this riddle correctly?
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It has too many tellers Did you answer this riddle correctly?
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