Which is the correct shadow of the bird?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

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

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

There are four 3-link chains. All you have to do is join them into a big 12-link chain. For joining two closed links, one of the links must be cut and placed onto the other link for closing.

How many minimum links will you have to cut to make the big chain?

How many times can you subtract the number 5 from 25?

What has one letter and starts with an E?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?