Two stores A and B are promoting the same brand of sneakers with a price tag of 350 yuan. The plan is as follows: Buy in store A and enjoy "discount up" (i.e. 40% off first, then 10% off on top of that.) B Stores are over 300 yuan minus 200 yuan. Ask which store is cheaper? How much is it cheaper?
甲、乙两家商店对标价为350元的同一品牌球鞋搞促销，方案如下：在甲商店购买享受"折上折"，(即先打六折，在此基础上再打九折．)乙商店则是满300元减200元．问哪个商店更便宜？便宜了多少元？
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">350 * (3/5) * (9/10)</gadget>
<output>189</output>

<gadget id="calculator">350 - 200</gadget>
<output>150</output>

<gadget id="calculator">189 - 150</gadget>
<output>39</output>

<result>39</result>