Ina class of 80 students, 60% participate in games and the rest do not. The average weight of the former group is 5% more than that of the latter. If the average weigh to fall the students is $$51\frac{1}{2}$$ kg, then what is the average weight (in kg) of the former group ?

A

52.5

B

54.5

C

57.6

D

60