81 x 9 = 801. What must you do to make the this equation true?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

Can you find the next number in the sequence?

113 119 101 114 116 ?

Using Only Five 5's and any mathematical operator make sum as 37

Can you find the odd number in the following five choices?

1) 482636
2) 259807
3) 865195
4) 104739
5) 391744

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

A man fell off a smuggling boat into deep water. He could not swim and he was not wearing anything to keep him afloat. It took 30 minutes for the people on the boat to realize someone was missing. The missing man was rescued two hours later on the return trip. Why didn't he drown? Note:- He didn't know swimming, the sea was deep, and He wasn't holding anything

A woman lives in a Tall building thirty-six floors high and served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?