Xiao Ming reads a 240-page book and has read 30% of it. How many pages are left?
小明看一本240页的书，已看它的30%，还剩多少页没有看？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">240 * (7/10)</gadget>
<output>168</output>

<result>168</result>