Every moving body or an object has a momentum. The simplest way to calculate it is to multiply the mass of an object with its velocity (p = m•v). So, just after this ice skater finished her performance, her momentum was 63 kg•10.8 m/s which equals to 680.4 kg•m/s. Then, she was given a huge bouquet which changed her total mass and speed. The thing we need to know is that the momentum before receiving the bouqet and after that are the same. With the bouqet, the mass increased and now is 63 kg + 4.4 kg = 67.4 kg. If p=m•v, then v=p/m, so her new speed is 680.4/67.4 = 10.0949, or approximately 10.1 m/s.
