Can you complete the sequence puzzle?

AR TA GE CA LE VI LI _

There is a unique number which when multiplied by any number from 1 to 6, we will get the new number that contains the same digits only.

Can you find that number?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

In the image given, you can find several triangles. Can you count them all?

Two friends were stuck in a cottage. They had nothing to do and thus they started playing cards. Suddenly the power went off and Friend 1 inverted the position of 15 cards in the normal deck of 52 cards and shuffled it. Now he asked Friend 2 to divide the cards into two piles (need not be equal) with equal number of cards facing up. The room was quite dark and Friend 2 could not see the cards. He thinks for a while and then divides the cards in two piles.

On checking, the count of cards facing up is same in both the piles. How could Friend 2 have done it ?

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

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

The chance of Mr John winning the lottery is 10%. All participants lined up and Mr John is 4th in the row. The first three participants lose the lottery.

What is the chance of Mr John now?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

Take away the whole and some still remain. What is it?