(1)13.50+5.60=19.1(元); 答:买1个乒乓球拍和l筒乒乓球,一共19.1元. (2)19.80×2+12.70, =39.6+12.70, =52.3(元); 52.3>50, 答:小青有50元,买一副羽毛球拍和一筒羽毛球不够.