Can you figure out the answer to this riddle?

Question

You have two pieces of string each burns in one hour but they burn

irregularlly in terms of how many inches burn per minute anywhere along the

string, can you use the strings to time 45 minutes

Answer 1

light the first string (sting A) at both ends and the other string (string B) on only one end. String A will burn in half the time since it was lit from both ends, so when it burns up that is half an hour.  Once string A has burned up, light the other end of string B...it will take 15 minutes to catch up to the end that has been burning for the past half hour, and there you have 45 minutes when that occurs.

Answer 2

yes, yes i think i can

Answer 3

cut one 1/4 of the string