Once upon a time, the mouse and the cat were good friends. They hid a jar of oil in the ruined temple together and prepared to enjoy it together during the Chinese New Year. Rats always steal oil to eat in the name of inspection. The first time they ate (1/5) and 4 grams, the second time they ate the rest (1/4) and 3 grams, and the third time they ate The remaining (1/3) is 2 grams, and the remaining 18 grams are eaten for the fourth time. How many grams are there in the altar of oil that the cat and the mouse began to hide?
从前，老鼠和猫是好朋友，它们一起在破庙里藏了一坛油，准备过年时一起享用．老鼠总以检查为名私自偷油吃，第一次偷吃了(1/5)又4克，第二次偷吃了剩下的(1/4)又3克，第三次偷吃了剩下的(1/3)又2克，第四次吃完所剩下的18克．猫和老鼠开始藏的这坛油有多少克．
<gadget id="calculator">18 + 2</gadget>
<output>20</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">20 / (2/3)</gadget>
<output>30</output>

<gadget id="calculator">30 + 3</gadget>
<output>33</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">33 / (3/4)</gadget>
<output>44</output>

<gadget id="calculator">44 + 4</gadget>
<output>48</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">48 / (4/5)</gadget>
<output>60</output>

<result>60</result>