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

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

Complete the table series riddle by finding the number that can replace "??".

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?

What has many keys but can’t open a single lock?

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

The more of this there is, the less you see. What is it?

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

John is 45 years older than his son Jacob. If you find similarities between their ages, both of their ages contain prime numbers as the digits. Also, John's age is the reverse of Jacob's age.

Can you find their ages?

You are playing as white and given four rooks to checkmate the black king in four moves with the following rules 1. You can place one rook every move and ensure the black king should be in check position.2. After four moves the black king should be in the checkmate position.