During May Day, a shopping mall engaged in preferential activities and decided to let customers draw lots to decide discounts. A customer buys two kinds of goods, A and B, and gets discounts of 30% and 10% respectively.
Solution: Let the original price of one commodity be X yuan and the original price of another commodity be 500-x yuan.
0.7x+(500-x)*0.9=386
0.7x+450-0.9x=386
450-0.2x=386
0.2x=450-386
0.2x=64
x=320
500-320= 180 yuan
A: The original prices of these two commodities are 320 yuan and 180 yuan respectively.