Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

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

Akbar called Birbal and asked him to draw a line on the floor. He asked Birbal to make that line smaller without erasing it. Birbal smiled and did it before Akbar could blink his eyes.

How did he managed to do it?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Which part of London exists in France as well ?

Three cars are driving on a track that forms a perfect circle and is wide enough that multiple cars can pass anytime. The car that is leading in the race right now is driving at 55 MPH and the car that is trailing at the last is going at 45 MPH. The car that is in the middle is somewhere between these two speeds.
Right now, you can assume that there is a distance of x miles between the leading car and the middle car and x miles between the middle car and the last car and also, x is not equal to 0 or 1.
The cars maintain their speed till the leading car catches up with the last car and then every car stops. In this scenario, do you think of any point when the distance between any two pairs will again be x miles i.e. the pairs will be x distance apart at the same time ?

The Little ant seems to be always confused. Do you know why?

Can you solve this tricky maths equation problem by replacing it? mark with the correct symbol?

19834 -----: 187
15921 -----: 153
17561 -----: 139
13734 -----: ???

I’m tall when I’m young, and I’m short when I’m old. What am I?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?