To attend world science seminar, A famous chemist from Mexico visit
London. In the lab, the scientist was killed and his six assistants were under suspicion of killing the chemist.
Name of six assistants: Austin, Wayne, Dege, Oscaru, Lingard, and Rojo.
He left a note "76-20-44 79-16-22-7"

A local detective Jack was called to solve the case,

After reading the note, Jack instantly asked the police to arrest the murderers.

Who are the murderers?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

Prove that twice of ten is the same as twice of eleven.

Samuel was out for a walk when it started to rain. He did not have an umbrella and he wasn't wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?

Can you count the number of triangles in the given figure?

0 0 0 = 6
1 1 1 = 6
2 2 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

You can use any mathematical symbols in the space provided to make all above algebraic expressions true.

I am white when I am dirty, and black when I am clean. What am I?

How can you make number one disappear by adding something to it?

The following alphametic has only one solution. Can you find it?
ENLIST + SILENT + LISTEN = ANAGRAM

PS: You may start the number from 0.

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?