For the health and safety of the students, the school decided to provide each dormitory student with a water cup, each of which costs 3.5 yuan. For this kind of water cup, Supermarket A offers a 10% discount, and Supermarket B buys 8 and gets 1 free. The school needs to buy 360 water glasses, please do the math, which supermarket can the school buy cheaply? How much cheaper?
为了学生的卫生安全，学校决定给每个住宿生配一只水杯，每只水杯3.5元．这种水杯，甲超市打九折，乙超市买8只送1只．学校需要买360只水杯，请你算一算，学校到哪家超市买便宜？便宜多少钱？
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">3.5 * (9/10) * 360</gadget>
<output>1_134</output>

<gadget id="calculator">8 + 1</gadget>
<output>9</output>

<gadget id="calculator">360 / 9</gadget>
<output>40</output>

<gadget id="calculator">360 - 40</gadget>
<output>320</output>

<gadget id="calculator">320 * 3.5</gadget>
<output>1_120</output>

<gadget id="calculator">1_134 - 1_120</gadget>
<output>14</output>

<result>14</result>