Subtract 30 times 1.3 from 219, the difference is (3/4) of a number, find this number.
219减去1.3的30倍，所得的差是一个数的(3/4)，求这个数．
<gadget id="calculator">1.3 * 30</gadget>
<output>39</output>

<gadget id="calculator">219 - 39</gadget>
<output>180</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">180 / (3/4)</gadget>
<output>240</output>

<result>240</result>