Random Puzzles 

Workings

Hint
Try working backwards.

Answer
15.

Reasoning
One quarter of 360 is 90.

One third of 90 is 30.

One half of 30 is 15.

Workings

Hint
'in the back of the net' begins with the letter G.

Answers
good = not bad
wood = forest
wool = sock material
cool = not hot
cowl = hooded robe
coil = spiral of wire
soil = earthy ground
foil = roasting metal
foal = baby horse
goal = in the back of the net

Workings

Hint
The clue is in the question.

Answer
B.

Reasoning
These are the initial letters of the puzzle itself:
   This
   is
   a
   very
   special
   sequence
   and
   is
   complete
 * but
   what
   is
   the
   missing
   letter

Therefore, B is missing.

Workings

Hint
Look at Digit 3 first.

Answer
6394.

Reasoning
Labelling the clues:

Digit 2 is smaller than Digit 4 Digit 4 is two thirds of Digit 1 Digit 1 is two thirds of Digit 3 Digit 3 is three times Digit 2
By (3), Digit 3 is divisible by 3:

   Digit 3 = 3, 6, 9

By (3), Digit 1 is two thirds of Digit 3:

   Digit 1 = 2, 4, 6.

But, by (2), Digit 1 is divisible by 3:

   Digit 1 = 6, and Digit 3 = 9.

By (4), Digit 3 is three times Digit 2:

   Digit 2 = 3.

By (2), Digit 4 is two thirds of Digit 1:

   Digit 4 = 4.