If 21x = 79x, what is the value of x?

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

If in a car race, the man who came two places in front of the last man finished one ahead of the man who came fifth, how many contestants were there?

A tourist visits a small town for his research. While in the town, he decides to get a haircut. Since the town is quite small, there are only two barbers in the town � one on the North Street and one on the South Street. The barbershop on the North Street is a mess and the barber has a weird and pathetic haircut. While the barbershop at the South Street is pretty tidy and the barber as well has an impressive haircut.

Which barbershop will the tourist visit for his haircut and why?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

In The 1st month of this year(the year 2013), I noticed that the date 13-1-13 (13 January 2013) is special.

This date is special as:

Date * Month = Year.

Can you figure out which year of this century has a maximum number of such dates?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

Sherlock Holmes was challenged to make a pre-drawn line smaller without erasing it. He did it in fractions of seconds. How?

A small town is visited by an ice-cream truck every day. On the first day of February, the truck visits as usual and 5 children, one from each of the first 5 houses on the street buys an ice cream that is of the different flavor from each other along with a completely different topping.

Go through the details below and find out which child lives in which house and bought which ice-cream flavor with which topping:

1. Jim lives between the child who bought the Raspberry topping and the child who bought mango ice cream.

2. Joyce, whose house has an even number, bought the cherry topping. Nancy does not live next to Joyce.

3. The blackcurrant ice cream had no topping.

4. The child who lives in house number 2 had the butterscotch ice cream. The child in house number 3 did not have chocolate ice cream.

5. Mike had banana ice cream. He hates banana cherry.

6. The child who had the cashew topping lives in house number 5. Dustin does not live in house number 4.

Please note that the odd numbered houses and the even numbered houses are located on the exactly opposite sides of the street.