Riddle #835


Past the Bridge Guard

A guard is stationed at the entrance to a bridge. He is tasked to shoot anyone who tries to cross to the other side of the bridge, and to turn away anyone who comes in from the opposite side of the bridge. You are on his side of the bridge and want to escape to the other side. Because the bridge is old and rickety, anyone who tries to cross it does so at a constant speed, and it always takes exactly 10 minutes to cross. The guard comes out of his post every 6 minutes and looks down the bridge for any people trying to leave, and at all other times he sits in his post and snoozes. You know you can sneak past him when he's sleeping, but the problem is that you won't be able to make it all the way to the other side of the bridge before he sees you (since he comes out every 6 minutes, but it takes 10 minutes to cross). One day a brilliant idea comes to you, and soon you've successfully crossed to the other side of the bridge without being shot. How did you do it?
Right after the guard goes back to his post after checking the bridge, you sneak by and make your way down the bridge. After a little bit less than 6 minutes, you turn around and start walking back toward the guard. He will come out and see you, and assume that you are a visitor coming from the other side of the bridge, since you're only about 4 minutes from the end of the other side of the bridge. He will go back into his post since he doesn't plan to turn you away until you reach him, and then you turn back around and make your way the rest of the way to the other side of the bridge.
87.96 %
47 votes

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We all know that square root of number 121 is 11. But do you know what si the square root of the number "12345678987654321" ?
111111111 Explanation: It's a maths magical square root series as : Square root of number 121 is 11 Square root of number 12321 is 111 Square root of number 1234321 is 1111 Square root of number 123454321 is 11111 Square root of number 12345654321 is 111111 Square root of number 1234567654321 is 1111111 Square root of number 123456787654321 is 11111111 Square root of number 12345678987654321 is 111111111 (answer)
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There are 4 big houses in my home town. They are made from these materials: red marbles, green marbles, white marbles and blue marbles. Mrs Jennifer's house is somewhere to the left of the green marbles one and the third one along is white marbles. Mrs Sharon owns a red marbles house and Mr Cruz does not live at either end, but lives somewhere to the right of the blue marbles house. Mr Danny lives in the fourth house, while the first house is not made from red marbles. Who lives where, and what is their house made from ?
From, left to right: #1 Mrs Jennifer - blue marbles #2 Mrs Sharon - red marbles #3 Mr Cruz - white marbles #4 Mr Danny - green marbles If we separate and label the clues, and label the houses #1, #2, #3, #4 from left to right we can see that: a. Mrs Jennifer's house is somewhere to the left of the green marbles one. b. The third one along is white marbles. c. Mrs Sharon owns a red marbles house d. Mr Cruz does not live at either end. e. Mr Cruz lives somewhere to the right of the blue marbles house. f. Mr Danny lives in the fourth house g. The first house is not made from red marbles. By (g) #1 isn't made from red marbles, and by (b) nor is #3. By (f) Mr Danny lives in #4 therefore by (c) #2 must be red marbles, and Mrs Sharon lives there. Therefore by (d) Mr Cruz must live in #3, which, by (b) is the white marbles house. By (a) #4 must be green marbles (otherwise Mrs Jennifer couldn't be to its left) and by (f) Mr Danny lives there. Which leaves Mrs Jennifer, living in #1, the blue marbles house.
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Breaking the Sound Barrier

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