Xiao Ming read 90 pages today, less than yesterday (4/9). Question: How many pages did Xiao Ming read yesterday?
小明今天看书90页，比昨天少(4/9)．问：小明昨天看书多少页？
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">1 - (4/9)</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">90 / (5/9)</gadget>
<output>162</output>

<result>162</result>