Prove that twice of ten is the same as twice of eleven.

Which is Odd One Out and why?

4377

3954

9862

8454

9831

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

Can you name three consecutive days without using the words Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, or Sunday?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

What number comes next in the series?

5 15 5 18 5 24 14 20 _