A girl has as many brothers as sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

Move three sticks of the spiral below to form a square.

2, 3, 5, 9, 17, _ What is the next number in the sequence?

Complete the table series riddle by finding the number that can replace "??".

A bank customer had $100 in his account. He then made 6 withdrawals. He kept a record of these withdrawals, and the balance remaining in the account, as follows:

Withdrawals Balance left
$50 $50
$25 $25
$10 $15
$8 $7
$5 $2
$2 $0
----- -----
$100 $99

Why are the Totals not tallying?

What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

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