Welcome "May 1st" promotion, the original price of Pepsi is 4 yuan a bottle. Supermarket A "buy 10 get 3 free"; Supermarket B sells at 30% off. Class No. 6 and No. 2 need to buy 40 bottles of Coke, which supermarket is the most cost-effective?
迎"五一"进行促销，百事可乐原价为4元一瓶．A超市"买10赠3"；B超市打七折销售．六二班要买40瓶可乐在哪家超市买比价合算？
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">40 * 4 * (7/10)</gadget>
<output>112</output>

<result>112</result>