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

Write the next letter in this sequence.
O, T, T, F, F, S, S, E, __
**Hint: It is a Number Series Puzzle

The more you take me, the more you leave me behind.
Who Am I?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

I know a country, If you remove the last alphabet of its name, it will become a part of your body. Do you name it?

Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

There are seven sisters in a house in a village where there is no electricity or any gadget.

Sister-1: Reading Novel
Sister-2: Cooking
Sister-3: Playing Chess
Sister-4: Playing Sudoku
Sister-5: Washing clothes
Sister-6: Gardening

what is Sister-7 doing ?

If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?