Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

It belongs to you, but other people use it more than you do. What is it?

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

Can you find a rabbit in the given picture?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

Replace the question mark with the correct number, given the pair of numbers exhibits a similar relationship?

? : 3839 :: 11 : 1209

What Time Should the last watch show in the below figure?

Women do it once a year after they turn 19 but men get to do it only once in a lifetime. What is it?