Random Puzzles 

Workings

Hint
Where do they each grow?

Answer
Potato.

This is the only one that grows underground.

Workings

Hint
The answer is a whole number less than 10.

Answer
3.

Reasoning
We can multiply throughout by 12,
    X     X     X     X
    -  -  -  +  -  =  -
    X     2     4     12

to give:

   12 − 6X + 3X = X

        12 − 3X = X

             12 = 4X

              3 = X

As required.

Double-Checking
    3     3     3     3
    -  -  -  +  -  =  -
    3     2     4     12

    1 − 1.5 + 0.75 = 0.25

              0.25 = 0.25, which confirms that 3 is correct.

Workings

Hint
Think about the first digits of the numbers.

Answer
There are more 2's because of the numbers beginning with 20,000.

Workings

Hint
The first digit represents something, the second digit represents something else.

Answer
93.

The first digit is how many letters there are in the word, the second digit is how many vowels (AEIOU) there are.