The US dollar continuing its winning streak in interbank trading gained 11 paisas against the Pakistani rupee and reached Rs280.20 on Friday. On Thursday, the American currency got a boost of 37 paisas against the Pakistani Rupee in the interbank market and started trading at Rs280.25. In the open market, however, the greenback remained stable at Rs282. On Wednesday, the US dollar closed the trading session at Rs279.88 in the interbank market. On the other hand, the KSE-100 index reached 51,226 with an increase of 42 points in the Friday morning trading session.