What double is 15 less than 25 4.6, find this number.
什么数的2倍比25个4.6少15，求这个数．
<gadget id="calculator">4.6 * 25</gadget>
<output>115</output>

<gadget id="calculator">115 - 15</gadget>
<output>100</output>

<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<result>50</result>