1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Can you decipher the below rebus?

PBLUESAISNUERSES

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

How many times can you subtract the number 5 from 25?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

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

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.