Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

A mathematician couple was having a Frappuccino in Starbucks sitting opposite to each other. Suddenly the guy noticed the text written on the paper in front of them and exclaimed that it was wrong. The girl denied it and said it is appropriate. Both are correct. What is written on the paper?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

A detective visits his friend John just to discover that John's neighbour Dr Jacob was murdered. Dr Jacob, who is a mathematician wrote the murderer's name in a code word "Hcqtfz". There were five suspects
1. Ajit
2. Pankaj
3. Ganpat
4. Deenu
5. Hariya

The Detective was instantly able to find the murderer.
Can you?

Before Balboa discovered the Pacific Ocean, which was the largest ocean before that?

Solve the following series:
AZ, GT, MN, __, YB

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?