When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

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 ?

John: "Hi Teacher, What is your favourite movie ?".
Chemistry Teacher: "Indium Cerium Platinum Iodine Oxygen Nitrogen".
Ten seconds later... John replied I got it.

Do you?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

Replace the 'X' with any mathematical symbol to make the expression equal to 111.

18 X 12 X 2 X 3 = 111

I am an odd number. Take away a letter and I become even. What number am I?

If a shopkeeper can only place the weights on one side of the common balance. For example, if he has weights 1 and 3 then he can measure 1, 3 and 4 only. Now the question is how many minimum weights and names of the weights you will need to measure all weights from 1 to 1000? This is a fairly simple problem and very easy to prove also.

In the following series, a set of numbers is progressing with a particular pattern. Can you deduce that pattern and find the missing set?

(2 + 6), (21 + 6), (58 + 6), (119 + 6), ___

You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?

DONALD
+GERALD
=ROBERT

Who has married many women but was never married?