I agree with SwissPete's answers from 2011. Saying that the price of fuel increased three times says absolutely nothing about how much it increased, just that there were three increases of some amount.
If you say "the price of fuel increased to three times," I think you have to add what it is three times of: "The price of fuel increased this month to three times its price in December."
I would not say "increased by three times" under any circumstances I can think of.
If I were actually saying this, I would go with the unambiguous "The price of fuel tripled [or quadrupled, whatever you actually mean] this month."
3배가격으로 오르다 에는 원래 기준을 설명해주어야 함.
to three times its price in June