Prices of petrol and diesel continued to be slashed marginally on Monday with a dip of Rs 0.17 and Rs 0.15 respectively, a litre in Delhi, according to a notification by oil-producing firms. Petrol was pegged at Rs 77.56 a litre and diesel at Rs 72.31 per litre. Meanwhile, in Mumbai, petrol was being sold for Rs 83.07 per litre and diesel at Rs 75.76, a decrease of Rs 0.17 a litre and Rs 0.16 a litre, respectively.