Move four matchsticks to the below square to form three squares?

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: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

Imagine a box with two cogwheels, one big with 24 teeth and one small with 8 teeth. The big one is firmly attached to the center of the box which means it does not turn or move while the small one rotates around the big one.

How many times do you think that the smaller wheel will turn compared to the box when it turns once around the big one?

John bought a new car. He has a habit of eating ice cream from a particular ice cream shop while returning home from office. Whenever, he eats strawberry ice cream, he faces no problem. But whenever, he eats chocolate ice cream, the car starts giving problem. At first, he thinks, it is just a co-incidence but when this awkward incident happens for 3-4 times, he reports this problem to the company.

The mechanic of the company checks but finds no problem at all. The next day, when he stops by to eat chocolate ice cream, the car again starts giving problem.

Can you find the possible reason?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

why number 8549176320 is one of a kind?

I have an eye but still cannot see.

Who am I?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

I cannot talk, but I always reply when spoken to. What am I?