A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?
One evening there was a murder in the home of a married couple, their son and daughter. One of these four people murdered one of the others. One of the members of the family witnessed the crime.
The other one helped the murderer.
These are the things we know for sure:
1. The witness and the one who helped the murderer were not of the same sex.
2. The oldest person and the witness were not of the same sex.
3. The youngest person and the victim were not of the same sex.
4. The one who helped the murderer was older than the victim.
5. The father was the oldest member of the family.
6. The murderer was not the youngest member of the family.
A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?
