YOU ARE ASLEEP AND THERE IS A SUDDEN KNOCK ON THE DOOR BEHIND THE DOOR ARE YOUR PARENTS WHO CAME TO HA RIDDLES WITH ANSWERS TO SOLVE - PUZZLES & BRAIN TEASERS

The answer is to let your friend go first. This puzzle is based on an old game/scam called Penny Ante. No matter what you picked, your friend would be able to come up with a combination which would be more likely to beat yours. For example, if you were to choose HHH, then unless HHH was the first combination to come up you would eventually lose since as soon as a Tails came up, the combination THH would inevitably come up before HHH. The basic formula you can use for working out which combination you should choose is as follows. Simply take his combination (eg. HHT) take the last term in his combination, put it at the front (in this case making THH) and your combination will be more likely to come up first. Try it on your friends! Did you answer this riddle correctly?
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1 in 3.

Since my brother has blue eyes (bb), both of my parents carry one brown and one blue gene (Bb). The three possibilities for my genotype, equally likely, are BB, Bb, and bB. Thus, there is a 2/3 chance that I carry a blue gene.

If I carry a blue gene, there is a 50% chance I will pass it on to my first child (and, obviously, 0% if I carry two brown genes).
Since my child will certainly get a blue gene from my wife, my gene will determine the eye color.

Multiplying the probabilities of those two independent events, there is a chance of 1/2 x 2/3 = 1/3 of my passing on a blue gene. Did you answer this riddle correctly?
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Those that remain behind must have written {1,4,6,8,9} and from this only {1,9} are odd. The probability of an odd number is thus 2/5.
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
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Time Did you answer this riddle correctly?
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Christmas cards Did you answer this riddle correctly?
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Silent Night Did you answer this riddle correctly?
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They'd both be safe because the lions that havent eaten in 3 months would be dead. Did you answer this riddle correctly?
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A foot Did you answer this riddle correctly?
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I am feet! Did you answer this riddle correctly?
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Never. The boat rises as the tide goes up. Did you answer this riddle correctly?
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He was bald. Did you answer this riddle correctly?
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Andrew. In the third line, and drew his name. It works better when you say it. Did you answer this riddle correctly?
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Because he is still alive! Did you answer this riddle correctly?
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An actor Did you answer this riddle correctly?
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A Grandfather Clock Did you answer this riddle correctly?
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