Seven nines written out in a series: 9 9 9 9 9 9 9. Put some “\(+\)” or “\(-\)” between some of them, so that the resultant expression equals 1989.
The tower clock chimes three times in 12 seconds. How long will six chimes last?
Fred always tells the truth, but George always lies. What question could you ask them so that they would give the same answer?
Jemima always tells the truth, but when she was asked the same question twice, she gave different answers. What kind of question could this be?
Woodchucks are sawing a log. They made 10 cuts. How many pieces were made?
A bagel is cut into sectors. Ten cuts were made. How many pieces did this make?
1. A bagel is cut into sectors. Ten cuts were made. How many pieces did this make?
2. Woodchucks are sawing a log. They made 10 cuts. How many pieces were made? How can we explain why the answers in the previous two questions are different?
Are the sum and product odd or even for:
a) two even numbers?
b) two odd numbers?
c) an odd and an even number?
In a race between 6 athletes, Andrew falls behind Boris and two athletes finish between them. Vincent finished after Declan, but before George. Declan finished before Boris but after Eric. Which order did the athletes finish the race in?
One person says: “I’m a liar.” Is he a native of the island of knights and liars?