A sells ten for two, so buy 50 plus 10, and you will get 60. 50*25= 1250.

B 60*25*80%= 1200

C first buy 48 pieces at 1.200 yuan, and the rebate is 1.80, plus 8 pieces in 20 yuan and 4 pieces in 70 yuan, 30 yuan, so the total * * * is 1.290 yuan, so the second method is the cheapest.