What is the difference between the product of 25 and 36 minus 16 nines?
25与36的积减去16个9，差是多少？
<gadget id="calculator">25 * 36</gadget>
<output>900</output>

<gadget id="calculator">16 * 9</gadget>
<output>144</output>

<gadget id="calculator">900 - 144</gadget>
<output>756</output>

<result>756</result>