A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

If "P" means "-", "Q" means "/", "R" means "+", and "S" means "*" then find the value of the following:

21 Q 7 R 9 S 10 P 13

There are hundred red gems and hundred blue gems. The blue gems are priceless while the red gems equal wastage. You have two sacks one labeled Heads and the other Tails. You have to distribute the gems as you want in the two sacks. Then a coin will be flipped and you will be asked to pick up a gem randomly from the corresponding sacks.

How will you distribute the gems between the sacks so that the odds of picking a Blue gem are maximum?

Who is that with a neck and no head, two arms and no hands? What is it?

Replace the question mark with the correct number in below Picture:

What does an Island and the letter T have in common?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

What do the following words have in common?

Assess
Banana
Dresser
Grammar
Potato
Revive
Uneven
Voodoo

John gave half of the apples he had plus one more to Jacob. He gave half of the remaining ones plus one more to James. Now, John was left with just one apple.

Can you find out how many did he have in the beginning?

I know a nine-letter word having only one vowel.
Do you ?