A professor thinks of two consecutive numbers between 1 and 10.

'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.

B: Neither do I know your number.

A: Now I know.

There are four solution for this.What are they ??

Difficulty ★★★★☆ Popularity ★★★★★

Outside a room there are three light switches. One of switch is connected to a light bulb inside the room.

Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb ??

Difficulty ★★★★☆ Popularity ★★★★☆

You can place weights on both side of weighing balance and you need to measure all weights between 1 and 1000. For example if you have weights 1 and 3,now you can measure 1,3 and 4 like earlier case, and also you can measure 2,by placing 3 on one side and 1 on the side which contain the substance to be weighed. So question again is how many minimum weights and of what denominations you need to measure all weights from 1kg to 1000kg.

Difficulty ★★★★☆ Popularity ★★★★★

2+3=8,

3+7=27,

4+5=32,

5+8=60,

6+7=72,

7+8=??

Solve it?

Difficulty ★★★★☆ Popularity ★★★★☆

A man who lives on the tenth floor takes the elevator down to the first floor every morning and goes to work. In the evening, when he comes back; on a rainy day, or if there are other people in the elevator, he goes to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment.

Can you explain why?

Difficulty ★★★☆☆ Popularity ★★★★☆

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

Difficulty ★★★★★ Popularity ★★★★★

You are given a set of scales and 12 marbles. The scales are of the old balance variety. That is, a small dish hangs from each end of a rod that is balanced in the middle. The device enables you to conclude either that the contents of the dishes weigh the same or that the dish that falls lower has heavier contents than the other.

The 12 marbles appear to be identical. In fact, 11 of them are identical, and one is of a different weight. Your task is to identify the unusual marble and discard it. You are allowed to use the scales three times if you wish, but no more.

Note that the unusual marble may be heavier or lighter than the others. You are asked to both identify it and determine whether it is heavy or light.

Difficulty ★★★★☆ Popularity ★★★★★

Two old friends, Jack and Bill, meet after a long time.

Three kids

Jack: Hey, how are you man?

Bill: Not bad, got married and I have three kids now.

Jack: That’s awesome. How old are they?

Bill: The product of their ages is 72 and the sum of their ages is the same as your birth date.

Jack: Cool… But I still don’t know.

Bill: My eldest kid just started taking piano lessons.

Jack: Oh now I get it.

How old are Bill’s kids?

Difficulty ★★★★★ Popularity ★★★★★

-> You are given 2 eggs.

-> You have access to a 100-storey building.

-> Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100 th floor.Both eggs are identical.

-> You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.

-> Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

Difficulty ★★★☆☆ Popularity ★★★★★

Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?