Novice handicapping question

[SuffolkGirl]

When I am reading the PPs and I look at the time intervals, that is the time for the first horse to hit that spot, the 1/4,1/2 etc. Right? And the finish time is the time the first horse stopped the clock. So, how did I figure out what the other horses ran? Is there a standard that I add to my horse's time, i.e. if he finishes 3rd by x lengths do I multiply a fractional figure times the number of lengths back to get his finish time? What about the splits, how do I calculate how fast one horse is going?

Any help is appreciated, I enjoy reading the Mysteries of the PPs and am sure that some day I can find the key to unlock it all!