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

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

Spot what is wrong here in below Picture?

You bought me for dinner but never eat me. What am I?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

In the attached figure, you can see a chessboard and two rooks placed on the chess board. What you have to find is the number of squares that do not contain the rooks. How many are there?

You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?

DONALD
+GERALD
=ROBERT

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

Eight of us go fourth, not back, to protect our king from an attack. What are we?