Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

Which Burger Is Different in below image?

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

You can find some missing letters in the picture. By placing two particular letters in the spaces, you can form a nine lettered word beginning from one of the corners and going clockwise direction to the middle. Can you find out the letters and the word?

Find the missing letter in the last circle logically in the given below picture.

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

Can you solve below mathematical equation?

2^1234 - 2^1233

What is the difference between a jeweller and a jailer?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?