One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

Solve the following series:
AZ, GT, MN, __, YB

A research team went to a village somewhere between the jungles of Africa. Luckily for them, they reached the day when quite an interesting custom was to be performed. The custom was performed once a year as they confirmed and was performed in order to collect the taxes from every male of the region.

The taxes were to be paid in the form of grains. Everyone must pay pounds of grain equaling his respective age. This means a 20-year-old will have to pay 20 pounds of grain and a 30-year-old will pay 30 pounds of grain and so on.

The chief who collects the tax has 7 weights and a large 2-pan scale to weigh. But there is another custom that the chief can weigh only three of the seven weights.

Can you find out the weights of the seven weights? Also, what is the maximum age of the man that can be weighed for the payment of taxes?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

A man lives on the fifteenth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator, or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up five flights of stairs to his apartment. Can you explain why he does this?

You need to arrange three 7 and mathematical symbols to form number 1?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

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?