Solution:

The peahen lays eggs

Solution:

He askes the god to beat him half to death.

Solution:

The brain teaser can be solved as shown in the image below.

Solution:

36 meters.

100/v1 = 80/v2
100/v2 = 80/v3

20+(20/v2)*v3=20+16 = 36

Solution:

100

Series of number that do not contain albhabet 'T'

Solution:

Move and then pour all juice from second glass to fifth glass.

Solution:

Playing chess

Game needs two players so Brother-8 is playing chess with Brother-2

Solution:

This statement is true but only in a specific case i.e. if both of the siblings continue to live till the day the younger is as old as the elder one was during the time of their birth.

Solution:

99 matches.

The number of matches will always sum up to one less than the number of players in a knock out tournament. You may calculate it in any manner. Thus 99 matches were played.

Solution:

8/(1−1/5)

Solution:

2003.

Explanation:
Its a series of prime numbes.