How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

Two fathers and two sons decided to go to a shop and buy some sweets upon reaching. Each of them bought 1 kg of sweet. All of them returned home after some time and found out that they had 3kg of sweets with them.

They did not eat the sweets in the way, nor threw or lose anything. Then, how can this be possible?

What does this mean?

CCCCCCC

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

How do you go from 98 to 720 using just one letter?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

Can you identify the hidden rebus in the image below?

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