Mingmingjia ordered 3 bags of milk every day in April, and paid a total of 76.5 yuan at the wholesale price. If the retail price of each bag of milk is 1.05 yuan, how much is each bag cheaper than the retail price?
明明家四月份每天预订3袋牛奶，按批发价共付76.5元，如果每袋牛奶的零售价是1.05元，那么每袋比零售价便宜多少元？
<gadget id="calculator">76.5 / 3 / 30</gadget>
<output>0.85</output>

<gadget id="calculator">1.05 - 0.85</gadget>
<output>0.2</output>

<result>0.2</result>