A bag of rice weighs 50 kilograms. The first time you eat it (1/10), the second time you eat it is the first time (4/5). How many kilograms are left uneaten?
一袋大米重50千克，第一次吃去(1/10)，第二次吃去的是第一次的(4/5)，还剩多少千克没吃？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">50 * (1/10)</gadget>
<output>5</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">50 * (1/10) * (4/5)</gadget>
<output>4</output>

<gadget id="calculator">50 - 5 - 4</gadget>
<output>41</output>

<result>41</result>