If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

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

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

What has one letter and starts with an E?

Seven Robbers robbed a bank and hide the coins in a lonely place.
They decide to divide the money equally the next morning. Two greedy robbers decided to cheat the others and reach the place at night. They equally divided the coins between them, one coin left. So they called another robber and then they decided to divide equally among the three. Sadly again one coin left. The same thing happened to the 4th 5th and the 6th robber.
However, when the 7th robber reached in the morning, they can divide the coins equally.

How many coins were there in total?

Before Mount Everest was discovered, what was the highest mountain in the world?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

What is more useful when it is broken?