(1/7) of a number is 15, what is this number?
一个数的(1/7)是15，这个数是多少．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">15 / (1/7)</gadget>
<output>105</output>

<result>105</result>