A Special Integer Riddle
A special integer exists in mathematics that shows a special property. If you subtract any number from that integer, the result will always be divisible by the successor of that number completely.
Do you know what that integer is ?
Do you know what that integer is ?
Hint:
The required integer is -1.
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
A Rickety Bridge Riddle
Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?
Hint:
17 mins.
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
Math Wiz Angel Riddle
Hint:
Late Home Work Riddle
Hint:
Age Of Three Daughters Riddles
I was visiting a friend one evening and remembered that he had three daughters. I asked him how old they were. The product of their ages is 72, he answered. Quizzically, I asked, Is there anything else you can tell me? Yes, he replied, the sum of their ages is equal to the number of my house. I stepped outside to see what the house number was. Upon returning inside, I said to my host, Im sorry, but I still cant figure out their ages. He responded apologetically, Im sorry, I forgot to mention that my oldest daughter likes strawberry shortcake. With this information, I was able to determine all three of their ages. How old is each daughter?
Hint:
3, 3, and 8. The only groups of 3 factors of 72 to have non-unique sums are 2 6 6 and 3 3 8 (with a sum of 14). The rest have unique sums:
2 + 2 + 18 = 22
2 + 3 + 12 = 18
2 + 4 + 9 = 15
3 + 4 + 6 = 13
The house number alone would have identified any of these groups. Since more information was required, we know the sum left the answer unknown. The presence of a single oldest child eliminates 2 6 6, leaving 3 3 8 as the only possible answer. Did you answer this riddle correctly?
YES NO
2 + 2 + 18 = 22
2 + 3 + 12 = 18
2 + 4 + 9 = 15
3 + 4 + 6 = 13
The house number alone would have identified any of these groups. Since more information was required, we know the sum left the answer unknown. The presence of a single oldest child eliminates 2 6 6, leaving 3 3 8 as the only possible answer. Did you answer this riddle correctly?
YES NO
The Upset Sergeant Riddle
Hint:
Shoe Guy Scarf Riddle
Hint:
43. Shoe (5) + Man, two scarves and two shoes (19) times scarf (2).
19 x 2 is 38. 38 + 5 is 43. Did you answer this riddle correctly?
YES NO
19 x 2 is 38. 38 + 5 is 43. Did you answer this riddle correctly?
YES NO
McDonalds Riddle
A brainteaser involving what looks like some simple math with McDonald's burgers and fries has left people starving for the correct answer. Can you solve this McDonalds riddle?
Hint: The key is to first determine how much each item is worth. The drink is clearly worth 10, and it's apparent from the second line that the burgers are worth five.
Pictures of the fries are each worth two, but you have to keep in mind that each individual packet of fries is worth one when you get to the next line. That has baited people into thinking, incorrectly, that the last line is 5 + 2 x 10.
The fourth line has also thrown many people off because it involves order of operations after already including the tricky single packet of fries.
Multiplication comes before addition, so you have to multiply one packet of fries by one drink and then add that to one burger. Thus, 5 + (1x10) = 15. Did you answer this riddle correctly?
YES NO
The fourth line has also thrown many people off because it involves order of operations after already including the tricky single packet of fries.
Multiplication comes before addition, so you have to multiply one packet of fries by one drink and then add that to one burger. Thus, 5 + (1x10) = 15. Did you answer this riddle correctly?
YES NO
Two Ships Riddle
Two ships leave the port of San Diego, both sailing for the distant shores of Japan. Each ship plans to travel the same route, spending a two-week stopover in Tokyo before returning to California. The first ship churns through the sea at 35 miles per hour throughout the entire journey. The second ship moves slower, at just 30 mph. After two weeks in Tokyo, the captain of the second ship decides to run at a faster pace, moving at 40 mph for the entire return trip. Which ship arrives in San Diego first?
Hint:
The first ship!
First ship = d/35 + d/35 = 2d/35 = 0.0571d
Second ship = d/30 = d/40 = 70d/1200 = 0.058 Did you answer this riddle correctly?
YES NO
First ship = d/35 + d/35 = 2d/35 = 0.0571d
Second ship = d/30 = d/40 = 70d/1200 = 0.058 Did you answer this riddle correctly?
YES NO
Two Ships Riddle
Two ships leave the port of San Diego, both sailing for the distant shores of Japan. Each ship plans to travel the same route, spending a two-week stopover in Tokyo before returning to California. The first ship churns through the sea at 35 miles per hour throughout the entire journey. The second ship moves slower, at just 30 mph. After two weeks in Tokyo, the captain of the second ship decides to run at a faster pace, moving at 40 mph for the entire return trip. Which ship arrives in San Diego first?
Hint:
The first ship!
First ship = d/35 + d/35 = 2d/35 = 0.0571d
Second ship = d/30 = d/40 = 70d/1200 = 0.058 Did you answer this riddle correctly?
YES NO
First ship = d/35 + d/35 = 2d/35 = 0.0571d
Second ship = d/30 = d/40 = 70d/1200 = 0.058 Did you answer this riddle correctly?
YES NO
The Start Of Nothing Logic Riddle
Hint: It's in plain sight
Always Coming But Never Arrives
Hint: A mythical land where 99% of all human productivity, motivation and achievement is stored.
Three Men On A Boat
Hint: They have to use the boat.
They throw one cigarette overboard and made the boat a cigarette lighter. Did you answer this riddle correctly?
YES NO
YES NO
Longest Human Nose Riddle
Hint:
You Answer Me
Hint:
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