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

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

Why is 6 afraid of 7?

In the image given, you can find several triangles. Can you count them all?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?

If,

A + B = C
D - C = A
E - B = C

Based on the above equations, find out the answer for:

D + F = ?

Which number should replace the question mark?

When monkey rotate the gear, which mark will be hit 1 or 2 ?

You bought me for dinner but never eat me. What am I?