06/03/2013 - Four 4s (10-19) (**)

This puzzle is rated 2 star (medium).

Description

During this puzzle you can only use the following mathematical functions:

• Addition
• Subtraction
• Multiplication
• Division
• Decimal point
• Square-root
• Brackets
• Power (e.g. 4 to the power 4 is 4 x 4 x 4 x 4 = 256)
• The number of 4 exactlyf 4 times.
  

Puzzle
Using only the mathematical functions and the number 4 (EXACTLY 4 times) construct the numbers from 10 to 19.

Check the solutions page for the correct answer.