The sum of 2 times of a number and its (1/4) is 90, find this number.
一个数的2倍与它的(1/4)的和是90，求这个数．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 + (1/4)</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">90 / (9/4)</gadget>
<output>40</output>

<result>40</result>