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

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

If,

A + B = C
D - C = A
E - B = C

Based on the above equations, find out the answer for:

D + F = ?

If a wheel has 54 spokes, how many spaces are there between the spokes?

I am working in a bus company. The company recently went under expansion and therefore there was not enough room for all the buses. As a result, twelve buses had to be stored outside.

If the company decides to expand the garage space by forty percent, enough space to accommodate the current buses will be created leaving enough space for twelve more buses if the need arises in future.

Can you calculate the number of buses that the company owns at present?

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?

Find the missing number in the sequence below:

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

I add 5 to 9 and get 2. The answer is correct, so what am I?