Can anyone tell me a word in the English dictionary which has a silent 'z'?

If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

They are three errirs in this question. Can you find them?

Jack and Joseph are well-known golf rivals. One Day during a match, they were level at a score of 30. Jack hit a bad shot and Joseph added 10 to his score. Joseph then hit an awesome shot and he won the game.

How ?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

By what process could you make a 'Tea-Table' into food?

Can you start the fire using two pieces of wood?

Paul's height is six feet, he's an assistant at a butcher's shop and wears size 9 shoes. What does he weigh?

What has a ring but no finger?