Terms & Conditions
I recently gave a new watch to my friend for their birthday. However, as usual with my presents, it was quite useless as it gains 6 minutes every hour. I set it using my own accurate clock at midnight and the watch now shows 8.26am. I know that it stopped 30 minutes ago, so what is the correct time now?
Hint: How many watch minutes will pass in a real hour?
Since the watch is gaining 6 minutes every hour, for every real hour that has passed, the watch will only show 66 minutes. Since the watch shows 8.26am, we know that 506 watch minutes have passed. This therefore equals 460 real minutes and hence 7 hours and 40 minutes. The watch stopped 30 minutes ago, therefore the time must now be 8.10am. QED.
My neighbour recently moved in down the road and has five children.
Unusually, half of the children are girls.
How can this be?
Hint: How many boys?
Answer: They are all girls.
On the island of Delzzup there are two types of inhabitants, knaves and knights.
Knaves always lie and knights always tell the truth.
Dave was having lunch with Darren but wasn't sure whether he was a knave or knight.
Dave decided to test Darren by asking him to ask the waiter whether he was a knave or a knight.
Darren said that the waiter had said that he was a knight.
Can you work out if Darren is a knave or a knight?
Hint: Think about this carefully.
Answer: Darren is a knight.
Darren asks the waiter "Are you a knight or a knave". If the waiter is a knight he will say so, but if he is a knave he will lie and still say he is a knight. Therefore the waiter will always reply that he is a knight. As Darren correctly tells Dave that the waiter said he was a knight, we know that Darren is a knight (but we know nothing of the waiter).
What is represented by this BrainBat?
Hint: Say what you see.