Petrol has become cheaper by 2 rupees 42 paise per litre and diesel by 2 rupees 25 paise per litre. The new rates have come into effect from midnight last night. According to Indian Oil Corporation, petrol in Delhi will now cost 56 rupees 49 paise a litre and in Chennai, 58 rupees 88 paise. In Mumbai, petrol will cost 63 rupees 90 paise a litre and in Kolkata, 64 rupees 60 paise. In Delhi, diesel will cost 46 rupees 01 paise, in Chennai 48 rupees 91 paise, in Mumbai 52 rupees 99 paise and in Kolkata, 50 rupees 99 paise per litre. This is the 10th straight reduction in petrol prices since August and the sixth in diesel since October, and is in line with fall in international crude oil prices.