Second pair: 240 is the selling price 120%, and 240 divided by 120%=200 yuan.
There are two ways to do this:
(1) The first pair of losses is 300-240=60 yuan.
The second pair earns 240-200=40 yuan.
60 yuan is bigger than 40 yuan.
Lost 20
②300+200=500 yuan 240+240=480 yuan.
500 yuan is bigger than 480 yuan.
Lost 20
But if there is no percentage sign after 20, it means that you don't make a profit or lose money.