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

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

When it is alive we sing, when it is dead we clap our hands. What is it?

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

What is common among 11, 69, and 88?

Which is the rope you never skip with?

When is the top of a mountain similar to a savings account?

Who always enjoys poor health?

Find the mistake in the below maths equations

A = 2
A(A-1) = 2(A-1)
A2-A = 2A-2
A2-2A = A-2
A(A-2) = A-2
A = 1