Can you fill the blank with the correct number?

6 30 870 756030 _____

What you cannot hold but it is yours?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Why is the Hole below a Lock?

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

Count the number of times the letter "F" appears in the following paragraph:

FAY FRIED FIFTY POUNDS OF
SALTED FISH AND THREE POUNDS
OF DRY FENNEL FOR DINNER FOR
FORTY MEMBERS OF HER FATHER'S FAMILY.

If a boy blows 18 bubbles,
Then pops 6 eats 7 and then
He pops 5 and blows 1.
How many are left?

Whats the next number in the below number sequence pattern.

What building has the most stories?

Find the hidden tiger in the given optical illusion ?