13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

Find the next number in the series below

21 32 54 87 131 ?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

Queen Elizabeth organised a royal party.

To Avoid uninvited guest royal family set a password.
Jack (an uninvited person) plan to enter the party. He stand nearby the door.

First guest comes, the security person said 'twelve' and guest replied with six.
Second guest comes , the security person said 'six' and guest replied with 'three'.

Jack thought is enough and he walked to the entry point. The security person said 'eight' , Jack replied smilingly 'four'.
He was immediately thrown out of the party. why ?

What does Alexander the Great and Winnie the Pooh have in common?

Which wheel of car does not rotate when you turn your car right?

Find out the number of circles in the given picture having Illusion

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

I have feet, but no legs. Which animal Am I?

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?