The product of (4/5) and (2/3) of a number is (9/10), what is this number?
一个数的(4/5)与(2/3)的积是(9/10)，这个数是多少？
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(4/5) * (2/3)</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">(9/10) / (8/15)</gadget>
<output>27/16 = around 1.6875</output>

<result>27/16 = around 1.6875</result>