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?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

Can you find out which number multiplied by itself will give the output as 12345678987654321?

The two towns are exactly 100 km apart. John leaves City A driving at 30 km/hr and Jacob leaves City B half an hour later driving at 60 km/hr. Who will be closer to City A when they meet?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

There is a basket full of hats. Three are white and two are black. Three men, Tom, Tim, and Jim, each take a hat out of the basket and put it on their heads without seeing the hat they selected or the hats the other men selected. The men arrange themselves so Tom can see Tim and Jim’s hats, Tim can see Jim’s hat, and Jim can’t see anyone’s hat. Tom is asked what color his hat is and he says he doesn’t know. Tim is asked the same question, and he also doesn’t know. Finally, Jim is asked the question, and he does know. What colour is his hat?

10+10 and 11+11 can give you the same answer.

Explain how?

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?