When 99 is considered higher than 100?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

The teacher told the student that if he told a lie then he will be expelled from school and if he told the truth then he still is expelled from school.

What can a student say to prevent his being expelled from school?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

As shown in the picture below, we can see a boy hanging on the tree branch to save his life. There are various ways in which he can die like1. A snake hanging toward the right waiting to bite the boy.2. A roaring Lion near the tree.3. Two crocodiles are ready to attack if the boy reaches near water. The tree is chopped to some extent, so can fall as if he moves a lot. Can you give this boy an escape plan?

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

What building has the most stories?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.