The sum of 2.5 times a number plus the quotient of 7 divided by 3.5 is 100. Find this number?
一个数的2.5倍加上7除3.5的商，和是100，求这个数？
<gadget id="calculator">3.5 / 7</gadget>
<output>0.5</output>

<gadget id="calculator">100 - 0.5</gadget>
<output>99.5</output>

<gadget id="calculator">99.5 / 2.5</gadget>
<output>39.8</output>

<result>39.8</result>