what's the probability of getting a king or a queen from a pack of 52 cards?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

Take one out and scratch my head, I am now black but once was red. What am I?

When we see 2 but call 10?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

How many letters are in the alphabet?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

There is a wide field of corn. A goose finds its way into the field and starts running. Can you find out till which point the goose can run into the field?