What four weights can be used to balance from 1 to 30 pounds?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

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

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

Birbal was jester, counsellor, and fool to the great Moghul emperor, Akbar.
The villagers loved to talk of Birbal's wisdom and cleverness,
and the emperor loved to try to outsmart him.
One day Akbar (emperor) drew a line across the floor.
"Birbal," he ordered, "you must make this line shorter, but you cannot erase any bit of it."
Everyone present thought the emperor had finally outsmarted Birbal.
It was clearly an impossible task.
Yet within moments the emperor and everyone else present had to agree that Birbal had made the line shorter without erasing any of it.
How could this be?

Can you solve the below rebus?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

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

A car meter reading shows 72927 miles a palindromic number.
what is the minimum number of miles you would need to travel to see another palindromic number on the car meter reading?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.