If 21x = 79x, what is the value of x?

There is a place where if I stand up straight, I will still be considered sideways.

Which is the smallest number that you can write using all the vowels exactly once?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

A network of 20 x 10 squares is given to you.

Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?

What occurs twice in a week, once in a year but never in a day?

When we see 2 but call 10?

Next Number in the Series,

5, 16, 49, 104, ?