If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

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

A tourist visits a small town for his research. While in the town, he decides to get a haircut. Since the town is quite small, there are only two barbers in the town � one on the North Street and one on the South Street. The barbershop on the North Street is a mess and the barber has a weird and pathetic haircut. While the barbershop at the South Street is pretty tidy and the barber as well has an impressive haircut.

Which barbershop will the tourist visit for his haircut and why?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

Rectify the following equality 101 - 102 = 1 by moving just one digit.