Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

Can you solve the below tricky visual equation?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

What Time Should the last watch show in the below figure?

What's a single-digit number with no value?

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

You have 1023 apples and 10 bags. You have to distribute these apples in these 10 bags in any way you choose. But when I ask for a certain number of apples you have to give them in terms of bags without transferring the apples from other bags. How do you distribute the apples?