Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Why 1729 is a magic number? Answer Logically.

In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.
ABCABA
BBDCAA
ABEABB
ABDBAA
------- +
AAFGBDH
What does the complete addition look like in digits?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

How can you tell a raw egg from a hard-boiled egg?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

Find out the missing number in the picture attached:

You are on a Boat in the mid of a river. You have two cigarettes with you. One of these two you have to light, how will you light the cigarette?

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?