title: How do I convert a hexadecimal number in IEEE 754 double precision (64bit) format to a decimal number?
body: <p>My task is to convert a hexadecimal number in double precision format (IEEE 754) on a paper.
  I've converted a hexadecimal number: 0x40790A0000000000 to a binary 64bit format so far and now I have: 
  0 10000000111 1001000010100000000000000000000000000000000000000000</p>
  
  <p>For the next step I am not totally sure what to do. I have to convert it into a decimal number and I've tried out several ways, but never got the right result.
  Hope you can help me and thank you.</p>