I am an odd number. Take away a letter and I become even. What number am I?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

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?

Find the Goldfish below the given Image.

In a town, there are four houses located at different distances from each other. Following are the distances:

The third house is 60 meters apart from the first house.
The fourth house is 40 meters apart from the second house.
The third house is 10 meters nearer to the fourth house than it is to the second house.

Can you find out the distance between the fourth and the first house?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

If you say my name, I will no longer exist. What am I?

Can you replace the question mark with the correct number?

Be active and find the killer in the picture Riddle below.