The small gear has 28 teeth, which is 1/5 of the number of the large gear. How many teeth does the large gear have?
小齿轮有28个齿，是大齿轮数的(1/5)，大齿轮有多少个齿？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">28 / (1/5)</gadget>
<output>140</output>

<result>140</result>