100 Widgets Riddle
If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?
Hint:
It would take 5 minutes. Each machine takes 5 minutes to make its widget. Therefore, each of the 100 machines would have finished making its widget in 5 minutes. Did you answer this riddle correctly?
YES NO
YES NO
100 Meter Sprint Riddle
Hint:
100 Lawyers Riddle
Hint:
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
Less Than 100 Riddle
Find a number less than 100 that is increased by one-fifth of its value when its digits are reversed.
Hint:
Crossing The Bridge Riddle
There are two villages separated with a river. Each day, four people cross the river through a bridge to work on the other side and earn for their families. On one night when they were returning from work, they noticed that the bridge was about to collapse. Now all of them wanted to cross the bridge before it collapsed as no one wanted to be stuck on that end without their families.
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
Hint:
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?
YES NO
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?
YES NO
150 Pens Riddle
Rihanna brought home 150 pens but while packing them, she misplaced some of them. When her brother asked how many she had misplaced, she told him:
If you count in pairs, one will remain
If you count in a group of three, two will remain
If you count in a group of four, three will remain
If you count in a group of five, four will remain
If you count in a group of six, five will remain
If you count in a group of seven, nothing will remain.
How many pens do you think has she misplaced ?
If you count in pairs, one will remain
If you count in a group of three, two will remain
If you count in a group of four, three will remain
If you count in a group of five, four will remain
If you count in a group of six, five will remain
If you count in a group of seven, nothing will remain.
How many pens do you think has she misplaced ?
Hint:
100 Billion Neurons Riddle
Hint:
The 100th Floor Riddle
A man lives on the 100th floor of his apartment building. Every day he takes the elevator down from his apartment to the lobby. After work, he takes the elevator from the lobby to the 50th floor and walks up the stairs the rest of the way. On rainy days he takes the elevator all the way from the lobby to the 100th floor. Why?
Hint:
The man was a dwarf. On rainy days he had an umbrella to help him press the button 100. Did you answer this riddle correctly?
YES NO
YES NO
108 Spiders Riddle
Hint:
The Protest Of 1773
Hint:
Dancing In 1776 Riddle
Hint:
100 Politicians Riddle
There is a party of 100 high-powered politicians. All of them are either honest or liars. You walk in knowing two things:
- At least one of them is honest.
- If you take any two politicians, at least one of them is a liar.
From this information, can you know how many are liars and how many are honest?
- At least one of them is honest.
- If you take any two politicians, at least one of them is a liar.
From this information, can you know how many are liars and how many are honest?
Hint:
Yes, from the information you know 1 is honest and 99 are liars.
One of them is honest satisfying the first piece of information. Then if you take the honest man and any other politician, the other politician must be a liar to satisfy the second piece of information, 'If you take any two politicians, at least one of them is a liar.' So 99 are liars. Did you answer this riddle correctly?
YES NO
One of them is honest satisfying the first piece of information. Then if you take the honest man and any other politician, the other politician must be a liar to satisfy the second piece of information, 'If you take any two politicians, at least one of them is a liar.' So 99 are liars. Did you answer this riddle correctly?
YES NO
100 Year Old Ant Riddle
Hint:
Adding To 1000 Riddle
Do this in your head don't use paper and pencil or a calculator just your mind.
Take 1000 and add 40. Now add 1000, add 30,add 1000, add 20, add 1000, add 10
what is your answer?
Take 1000 and add 40. Now add 1000, add 30,add 1000, add 20, add 1000, add 10
what is your answer?
Hint:
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